{ "data": { "a": { "slug": "assemblyai-stt", "name": "AssemblyAI Speech-to-Text (Universal)", "vendor": "AssemblyAI", "vendorUrl": "https://www.assemblyai.com", "kind": "model", "category": "speech-to-text", "summary": "Speech-to-text APIs for recorded audio and live streams, with speaker identification, translation and redaction options.", "url": "https://www.anchorterminal.com/tools/assemblyai-stt", "markdownUrl": "https://www.anchorterminal.com/tools/assemblyai-stt.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/assemblyai-stt.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/assemblyai-stt.json", "repo": "https://github.com/AssemblyAI/assemblyai-python-sdk", "license": "MIT (SDKs)", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.assemblyai.com/v2", "packages": [ { "registry": "npm", "name": "assemblyai" }, { "registry": "pypi", "name": "assemblyai" } ], "auth": "api-key", "authNotes": "API key in the `authorization` header. Temporary tokens for browser streaming. The docs MCP needs no key.", "pricing": "usage", "pricingNotes": "Free tier with no card covers up to 185 hours of pre-recorded or 333 hours of streaming. Then pay as you go per hour of audio. Universal-3.5 Pro $0.21, Universal-2 $0.15, Universal-3.6 Pro Realtime $0.45, Universal-Streaming $0.15, Sync $0.45. Diarisation $0.02 an hour on files and $0.12 on streams, keyterms $0.05 on Universal-3.5 Pro, translation $0.06. Streaming bills session time, not audio sent (https://www.assemblyai.com/pricing).", "priceSummary": "Pay per use", "where": "hosted", "x402": { "level": "no", "evidence": "No x402 or machine payment in the docs or pricing. Card or prepaid credits only (checked 2026-09-30).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 213, "npmWeekly": 599958, "pypiWeekly": 738086, "asOf": "2026-09-30" }, "docsUrl": "https://www.assemblyai.com/docs", "llmsTxt": "https://www.assemblyai.com/docs/llms.txt", "openapi": "https://www.assemblyai.com/docs/openapi.yaml", "capabilities": [ "speech.stt", "speech.streaming", "speech.batch", "speech.diarisation", "speech.languages", "speech.translation" ], "tags": [ "hosted", "no-card", "free-tier", "closed-source", "python", "typescript", "openapi", "llms-txt", "mcp", "streaming", "batch", "webhooks", "async-jobs", "enterprise" ], "lastRelease": "2026-09-24", "graded": true, "anchor": { "graded": true, "score": 66.8, "grade": "B", "agentReady": false, "rank": 272, "ranked": true, "rankOf": 950, "categoryRank": 11, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 80, "maintenance": 80, "payments": 40, "reliability": 70, "schema": 95, "security": 50, "transparency": 76 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": -3, "negativeNotes": [ "2026-07-10, the async `speech_model` parameter began returning 400 for current model names and silently routing legacy names to the default model, and `universal-3-pro` was blocked for new accounts and accounts inactive for 7 days, all announced in the changelog the same day. We found no earlier notice (https://www.assemblyai.com/changelog). Documented, so the minimum deduction." ], "verdict": "OpenAPI 3.1 file with typed inputs and error responses on every operation. Two outages of an hour or more in the last 90 days, on 31 July and 16 September 2026.", "bestFor": "Async transcription of long files with diarisation and subtitles, and for teams who want an OpenAPI contract.", "strengths": [ "OpenAPI 3.1 file with typed inputs and error responses on every operation", "Universal-2 covers 99 languages at $0.15 an hour, Universal-3.5 Pro is $0.21", "Transcript lists paginate with `limit`, `before_id` and `after_id`, and transcripts come back as sentences, paragraphs, SRT or VTT", "Free tier with no card, up to 185 hours pre-recorded", "TTL deletion from 1 hour and a delete endpoint for transcripts" ], "weaknesses": [ "Two outages of an hour or more in the last 90 days, on 31 July and 16 September 2026", "Free accounts can't opt out of model training", "The HTTP rate limit returns 403 with no Retry-After", "Streaming bills the time the socket is open, up to a 3-hour auto-close", "No security.txt or published disclosure policy" ], "agentNotes": [ "Send `{\"type\":\"Terminate\"}` to close every stream, or billing runs to the 3-hour auto-close", "Use `speech_models` (plural). The singular `speech_model` now returns 400 for current model names", "Treat a 403 on polling as the rate limit and back off with jitter, or use webhooks", "Fetch `/sentences` or `/paragraphs` instead of the full transcript when you only need text", "Opt out in Data Controls on a paid account before sending customer audio" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3.5, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 66.8 } ], "editorialScores": { "ergonomics": 80, "maintenance": 80, "payments": 40, "reliability": 70, "schema": 95, "security": 50, "transparency": 70 }, "provenanceScore": 81 }, "connect": { "http": "curl -X POST https://api.assemblyai.com/v2/transcript -H \"authorization: $ASSEMBLYAI_API_KEY\" \\\n -H \"content-type: application/json\" \\\n -d '{\"audio_url\":\"https://assembly.ai/wildfires.mp3\",\"language_detection\":true,\"speaker_labels\":true}'", "claudeCode": "claude mcp add assemblyai-docs --transport http https://assemblyai.com/docs/mcp" }, "letme": { "capability": "https://letme.dev/speech.stt", "tool": "https://letme.dev/assemblyai-stt" }, "sameCompany": [ "assemblyai-voice-agent" ], "area": "voice", "unitPrices": [ { "item": "Universal-3.5 Pro pre-recorded", "unit": "audio-minute", "usd": 0.0035, "note": "published as $0.21 an hour" }, { "item": "Universal-2 pre-recorded", "unit": "audio-minute", "usd": 0.0025, "note": "published as $0.15 an hour" }, { "item": "Universal-3.6 Pro Realtime", "unit": "audio-minute", "usd": 0.0075, "note": "published as $0.45 an hour, billed on session time" }, { "item": "Universal-Streaming", "unit": "audio-minute", "usd": 0.0025, "note": "published as $0.15 an hour, billed on session time" }, { "item": "Sync API", "unit": "audio-minute", "usd": 0.0075, "note": "published as $0.45 an hour, clips up to 2 minutes" }, { "item": "Streaming diarisation add-on", "unit": "audio-minute", "usd": 0.002, "note": "published as $0.12 an hour" } ], "provenance": { "legalEntity": "AssemblyAI, Inc.", "domain": "assemblyai.com", "domainRegistered": "2016-12-24", "endpointOnVendorDomain": true, "terms": "https://www.assemblyai.com/legal/terms-of-service", "privacy": "https://www.assemblyai.com/legal/privacy-policy", "statusPage": "https://status.assemblyai.com", "changelog": "https://www.assemblyai.com/changelog", "securityTxt": "none", "checked": "2026-09-30", "score": 81 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/assemblyai-stt.json", "live": { "slug": "assemblyai-stt", "probe": { "target": "https://api.assemblyai.com/v2", "method": "get", "lastAt": "2026-10-10T03:06:56.975286328Z", "lastOk": true, "lastStatus": 404, "lastMs": 439, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 446, "p95ms24h": 503, "samples24h": 249, "samples30d": 2468, "days": [ { "date": "2026-09-30", "probes": 35, "ok": 35 }, { "date": "2026-10-01", "probes": 276, "ok": 276 }, { "date": "2026-10-02", "probes": 248, "ok": 248 }, { "date": "2026-10-03", "probes": 271, "ok": 271 }, { "date": "2026-10-04", "probes": 272, "ok": 272 }, { "date": "2026-10-05", "probes": 272, "ok": 272 }, { "date": "2026-10-06", "probes": 272, "ok": 272 }, { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 250, "ok": 250 }, { "date": "2026-10-10", "probes": 32, "ok": 32 } ] }, "vendorStatus": { "page": "https://status.assemblyai.com", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-10T03:01:50.426504557Z" }, "versions": [ { "registry": "github", "name": "AssemblyAI/assemblyai-python-sdk", "version": "1.6.1", "released": "2026-09-24", "seenAt": "2026-10-09T16:40:27.755394594Z" }, { "registry": "npm", "name": "assemblyai", "version": "4.41.5", "seenAt": "2026-10-09T16:40:27.217227602Z" }, { "registry": "pypi", "name": "assemblyai", "version": "1.6.1", "released": "2026-09-24", "seenAt": "2026-10-09T16:40:27.644095501Z" } ], "githubStars": 213, "npmWeekly": 533880, "pypiWeekly": 779517, "securityTxt": { "url": "https://assemblyai.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-09T15:40:28.750839787Z" }, "llmsTxt": { "url": "https://www.assemblyai.com/docs/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-09T14:01:27.341480839Z" }, "domain": { "domain": "assemblyai.com", "registered": "2016-12-24", "source": "https://rdap.verisign.com/com/v1/domain/assemblyai.com", "checkedAt": "2026-10-04T13:07:48.940216522Z" }, "pages": [ { "url": "https://www.assemblyai.com/changelog", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:48:14.22020694Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "f7dbbe98a56a" }, { "url": "https://www.assemblyai.com/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:48:22.265212474Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "07bb01ccd4d1" }, { "url": "https://www.assemblyai.com/legal/privacy-policy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:48:18.643811376Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "6671be50624e" }, { "url": "https://www.assemblyai.com/legal/terms-of-service", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:48:20.297585473Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "766c6ee47ebc" } ], "updatedAt": "2026-10-10T03:06:56.975286328Z" } }, "answer": "Cartesia Ink scores 67.9 (B) on agent readiness against AssemblyAI Speech-to-Text (Universal)'s 66.8 (B), and leads in 3 of 7 scored categories. AssemblyAI Speech-to-Text (Universal) leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and transparency \u0026 trust.", "b": { "slug": "cartesia-ink-stt", "name": "Cartesia Ink", "vendor": "Cartesia", "vendorUrl": "https://www.cartesia.ai", "kind": "model", "category": "speech-to-text", "summary": "Cartesia's hosted speech-to-text API. Ink 2 transcribes live audio in five languages over a WebSocket with built-in turn detection, and the older Ink Whisper model transcribes uploaded files in about 100 languages.", "url": "https://www.anchorterminal.com/tools/cartesia-ink-stt", "markdownUrl": "https://www.anchorterminal.com/tools/cartesia-ink-stt.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/cartesia-ink-stt.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/cartesia-ink-stt.json", "repo": "https://github.com/cartesia-ai/cartesia-python", "license": "Proprietary hosted service under the Cartesia Terms of Service. The Python and JavaScript SDKs are Apache-2.0", "transports": [ "http", "websocket", "streamable-http" ], "remoteUrl": "https://api.cartesia.ai", "packages": [ { "registry": "pypi", "name": "cartesia" }, { "registry": "npm", "name": "@cartesia/cartesia-js" }, { "registry": "pypi", "name": "cartesia-mcp" } ], "auth": "api-key", "authNotes": "Self-serve API key (`sk_car_...`) from the Playground at play.cartesia.ai/keys, sent as `Authorization: Bearer` or `X-API-Key`. Browser clients use an access token with an `stt` grant, valid for at most one hour, passed as the `access_token` query parameter on WebSockets. Usage and key-metadata endpoints need a separate admin key (https://docs.cartesia.ai/use-the-api/api-conventions).", "pricing": "freemium", "pricingNotes": "Billed in credits. `ink-2` costs 3 credits a second of audio on both realtime endpoints, silence included. `ink-whisper` costs 1 credit a second in realtime and 1 credit per 2 seconds in batch (https://docs.cartesia.ai/pricing). Plans are Free ($0, 20,000 credits a month), Pro ($5, 100,000), Startup ($49, 1.25 million) and Scale ($299, 8 million), so an agent's owner can start without a contract. Commercial use starts at Pro (https://www.cartesia.ai/pricing).", "priceSummary": "Freemium", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the docs index, the pricing pages or the STT reference (checked 2026-10-09).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 134, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-09" }, "docsUrl": "https://docs.cartesia.ai/use-the-api/stt/compare-endpoints", "llmsTxt": "https://docs.cartesia.ai/llms.txt", "openapi": "https://docs.cartesia.ai/latest.yml", "capabilities": [ "speech.stt", "speech.streaming", "speech.batch", "speech.languages" ], "tags": [ "official", "hosted", "model", "closed-source", "streaming", "batch", "free-tier", "python", "typescript", "openapi", "llms-txt", "mcp", "status-page", "security-txt", "soc2", "enterprise" ], "lastRelease": "2026-09-17", "graded": true, "anchor": { "graded": true, "score": 67.9, "grade": "B", "agentReady": false, "rank": 238, "ranked": true, "rankOf": 950, "categoryRank": 9, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 74, "maintenance": 85, "payments": 35, "reliability": 73, "schema": 89, "security": 52, "transparency": 67 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-09" }, "negative": 0, "verdict": "Ink 2 streams transcripts with turn detection built into the model, documented by an AsyncAPI file with typed ranges and structured errors. The terms, last revised 14 June 2024, let Cartesia train on inputs and outputs unless the customer opts out, and zero data retention is an Enterprise setting. Ink 2 has no batch endpoint and no diarisation.", "bestFor": "Suited to voice agents that need turn detection and transcription from one model in English, French, Hindi, Japanese or Spanish, and to teams already using Cartesia text-to-speech.", "strengths": [ "`/stt/turns/websocket` emits `turn.start`, `turn.update`, `turn.eager_end`, `turn.resume` and `turn.end`, so no separate voice activity detector is needed", "OpenAPI and AsyncAPI files, llms.txt and Markdown twins of every docs page, with enums and numeric ranges on the WebSocket parameters", "Structured errors on `Cartesia-Version` 2026-03-01 and later, with `error_code`, `title`, `message`, `request_id` and an optional `doc_url`", "Short-lived access tokens (at most one hour) carry an `stt` grant, and admin keys are a separate key type from standard keys", "The status page lists Speech to Text in four regions, at 99.97% (US), 99.994% (EU and APAC) and 100% (AU) for July to October 2026" ], "weaknesses": [ "The terms let Cartesia train models on inputs and outputs unless otherwise agreed. Opting out is a form in the Playground's data controls", "Zero data retention is an Enterprise plan setting, and no retention period for other plans was found in the terms, privacy policy or docs", "`ink-2` supports English, French, Hindi, Japanese and Spanish only and has no batch endpoint. `POST /stt` accepts `ink-whisper` only", "No diarisation or speaker labels in the reviewed documentation, and realtime input is raw mono PCM with `encoding` and `sample_rate` required", "The terms of 14 June 2024 forbid automation software (bots) and any robot or scraper that accesses the Services to collect data, which matters before any probe is run", "No SLA was found, and a 429 for exceeding the concurrency limit is documented without a `Retry-After` header or backoff guidance" ], "agentNotes": [ "Use `wss://api.cartesia.ai/stt/turns/websocket` with `model=ink-2`, `encoding`, `sample_rate` and `cartesia_version=2026-08-14`. All four are required.", "Send raw mono audio in chunks of about 100 ms at the speed it was spoken. Pushing a whole file into the socket can return an internal server error.", "Read the final text from `turn.end` only. `transcript` is cumulative within a turn, so joining `turn.update` events duplicates text.", "Send `{\"type\": \"close\"}` after the last audio and keep reading until the server closes the socket, or the buffered tail is lost.", "Check `encoding` and `sample_rate` against the source before sending. The docs say the server might not return an error when they are wrong." ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 67.9 } ], "editorialScores": { "ergonomics": 74, "maintenance": 85, "payments": 35, "reliability": 73, "schema": 89, "security": 52, "transparency": 49 }, "provenanceScore": 84 }, "connect": { "install": "pip install 'cartesia[websockets]' # or: npm install @cartesia/cartesia-js", "claudeCode": "claude mcp add --transport http --scope user cartesia https://mcp.cartesia.ai/mcp" }, "letme": { "capability": "https://letme.dev/speech.stt", "tool": "https://letme.dev/cartesia-ink-stt" }, "sameCompany": [ "cartesia-tts", "cartesia-voice-cloning" ], "area": "voice", "unitPrices": [ { "item": "Ink 2 realtime, Scale plan", "unit": "audio-minute", "usd": 0.0067, "note": "180 credits a minute at $299 for 8M credits. Cartesia quotes $0.39 an hour" }, { "item": "Ink 2 realtime, Startup plan", "unit": "audio-minute", "usd": 0.0071, "note": "180 credits a minute at $49 for 1.25M credits" }, { "item": "Ink 2 realtime, Pro plan", "unit": "audio-minute", "usd": 0.009, "note": "180 credits a minute at $5 for 100,000 credits" }, { "item": "Ink Whisper realtime, Scale plan", "unit": "audio-minute", "usd": 0.0022, "note": "60 credits a minute at $299 for 8M credits" }, { "item": "Ink Whisper batch, Scale plan", "unit": "audio-minute", "usd": 0.0011, "note": "30 credits a minute at $299 for 8M credits" } ], "provenance": { "legalEntity": "Cartesia AI, Inc.", "domain": "cartesia.ai", "domainRegistered": "2023-05-10", "endpointOnVendorDomain": true, "terms": "https://www.cartesia.ai/legal/terms", "privacy": "https://www.cartesia.ai/legal/privacy", "statusPage": "https://status.cartesia.ai", "changelog": "https://docs.cartesia.ai/changelog/2026", "securityTxt": "valid", "checked": "2026-10-09", "score": 84 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/cartesia-ink-stt.json", "live": { "slug": "cartesia-ink-stt", "probe": { "target": "https://api.cartesia.ai", "method": "get", "lastAt": "2026-10-10T03:07:00.809061285Z", "lastOk": true, "lastStatus": 200, "lastMs": 126, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 69, "p95ms24h": 203, "samples24h": 117, "samples30d": 117, "days": [ { "date": "2026-10-09", "probes": 85, "ok": 85 }, { "date": "2026-10-10", "probes": 32, "ok": 32 } ] }, "vendorStatus": { "page": "https://status.cartesia.ai", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-10T03:01:52.995710279Z" }, "versions": [ { "registry": "github", "name": "cartesia-ai/cartesia-python", "version": "v4.2.0", "released": "2026-09-02", "seenAt": "2026-10-09T16:44:27.669680758Z" }, { "registry": "npm", "name": "@cartesia/cartesia-js", "version": "4.2.0", "seenAt": "2026-10-09T16:44:25.845737197Z" }, { "registry": "pypi", "name": "cartesia", "version": "4.2.0", "released": "2026-09-02", "seenAt": "2026-10-09T16:44:25.659263821Z" }, { "registry": "pypi", "name": "cartesia-mcp", "version": "0.26.1", "released": "2026-10-08", "seenAt": "2026-10-09T16:44:26.977578193Z" } ], "githubStars": 134, "npmWeekly": 79696, "pypiWeekly": 205864, "pages": [ { "url": "https://docs.cartesia.ai/changelog/2026", "kind": "changelog", "status": 200, "checkedAt": "2026-10-09T18:36:45.184290806Z", "changedAt": "2026-10-07T18:04:49.25388057Z", "fingerprint": "405fadad924b" }, { "url": "https://docs.cartesia.ai/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:36:47.532132362Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "379a41a8bcf3" }, { "url": "https://www.cartesia.ai/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-09T18:48:59.764022121Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "12bd9269bdef" }, { "url": "https://www.cartesia.ai/legal/privacy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-09T18:48:55.522982064Z", "changedAt": "2026-10-08T18:26:54.204830291Z", "fingerprint": "90fbd63881e5" }, { "url": "https://www.cartesia.ai/legal/terms", "kind": "terms", "status": 200, "checkedAt": "2026-10-09T18:48:57.753461207Z", "changedAt": "2026-10-08T18:26:56.591248396Z", "fingerprint": "2153bed03a23" } ], "updatedAt": "2026-10-10T03:07:00.809061285Z" } }, "facts": [ { "a": "Model API", "b": "Model API", "name": "Kind" }, { "a": "AssemblyAI", "b": "Cartesia", "name": "Vendor" }, { "a": "https://api.assemblyai.com/v2", "b": "https://api.cartesia.ai", "name": "Hosted endpoint" }, { "a": "HTTP, Streamable HTTP", "b": "HTTP, websocket, Streamable HTTP", "name": "Transports" }, { "a": "API key", "b": "API key", "name": "Auth" }, { "a": "Pay per use", "b": "Freemium", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "MIT (SDKs)", "b": "Proprietary hosted service under the Cartesia Terms of Service. The Python and JavaScript SDKs are Apache-2.0", "name": "Licence" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-09-24", "b": "2026-09-17", "name": "Last release" }, { "a": "2026-07-01", "b": "2024-06-14", "name": "Terms last updated" }, { "a": "2026-05-26", "b": "2024-06-14", "name": "Privacy policy last updated" }, { "a": "yes, with an opt-out", "b": "yes, with an opt-out", "name": "Customer content may train models" }, { "a": "yes", "b": "yes", "name": "Terms restrict automated access" }, { "a": "yes", "b": "yes", "name": "Terms restrict benchmarking" }, { "a": "not found in the text", "b": "not found in the text", "name": "Terms or service can change without notice" }, { "a": "not found in the text", "b": "yes", "name": "Arbitration or class-action waiver" }, { "a": "213 stars, 600k npm/wk, 738k PyPI/wk", "b": "134 stars", "name": "Popularity" }, { "a": "3.5/5 (2)", "b": "none", "name": "Agent reviews" } ], "faq": [ { "answer": "Cartesia Ink scores 67.9 (B) on agent readiness against AssemblyAI Speech-to-Text (Universal)'s 66.8 (B), and leads in 3 of 7 scored categories. AssemblyAI Speech-to-Text (Universal) leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and transparency \u0026 trust.", "question": "Which is better for AI agents, AssemblyAI Speech-to-Text (Universal) or Cartesia Ink?" }, { "answer": "Both need an API key.", "question": "Do AssemblyAI Speech-to-Text (Universal) and Cartesia Ink need an API key?" }, { "answer": "Yes. AssemblyAI Speech-to-Text (Universal) has a hosted endpoint at https://api.assemblyai.com/v2 and Cartesia Ink at https://api.cartesia.ai.", "question": "Can an agent call AssemblyAI Speech-to-Text (Universal) and Cartesia Ink without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Schema \u0026 documentation, 95 against 89", "Agent ergonomics, 80 against 74", "Payments \u0026 pricing, 40 against 35", "Transparency \u0026 trust, 76 against 67" ], "also": [ "Free to start without a card" ], "goodFor": "Async transcription of long files with diarisation and subtitles, and for teams who want an OpenAPI contract.", "slug": "assemblyai-stt", "watchFor": "Two outages of an hour or more in the last 90 days, on 31 July and 16 September 2026" }, { "aheadOn": [ "Maintenance \u0026 community, 85 against 80" ], "also": [ "No incidents deducted, where AssemblyAI Speech-to-Text (Universal) loses 3 points for them" ], "goodFor": "Suited to voice agents that need turn detection and transcription from one model in English, French, Hindi, Japanese or Spanish, and to teams already using Cartesia text-to-speech.", "slug": "cartesia-ink-stt", "watchFor": "The terms let Cartesia train models on inputs and outputs unless otherwise agreed. Opting out is a form in the Playground's data controls" } ], "job": { "capability": "speech.stt", "name": "Speech-to-text" }, "others": [ { "json": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-assemblyai-stt.json", "title": "Amazon Transcribe vs AssemblyAI Speech-to-Text (Universal)", "url": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-assemblyai-stt" }, { "json": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-cartesia-ink-stt.json", "title": "Amazon Transcribe vs Cartesia Ink", "url": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-cartesia-ink-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-azure-speech-to-text.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Azure AI Speech speech-to-text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-azure-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-deepgram-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Deepgram Speech-to-Text (Nova-3, Flux)", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-deepgram-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-elevenlabs-scribe.json", "title": "AssemblyAI Speech-to-Text (Universal) vs ElevenLabs Scribe Speech to Text API", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-elevenlabs-scribe" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-gladia-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Gladia Speech-to-Text API + MCP", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-gladia-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-google-speech-to-text.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Google Cloud Speech-to-Text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-google-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-groq-speech-to-text.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Groq Speech-to-Text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-groq-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-mistral-voxtral-transcribe.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Mistral Voxtral Transcribe", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-mistral-voxtral-transcribe" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-openai-speech-to-text.json", "title": "AssemblyAI Speech-to-Text (Universal) vs OpenAI Speech to Text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-openai-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-rev-ai-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Rev AI Speech-to-Text API", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-rev-ai-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-soniox-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Soniox Speech-to-Text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-soniox-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-speechmatics-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/azure-speech-to-text-vs-cartesia-ink-stt.json", "title": "Azure AI Speech speech-to-text vs Cartesia Ink", "url": "https://www.anchorterminal.com/compare/azure-speech-to-text-vs-cartesia-ink-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-deepgram-stt.json", "title": "Cartesia Ink vs Deepgram Speech-to-Text (Nova-3, Flux)", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-deepgram-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-elevenlabs-scribe.json", "title": "Cartesia Ink vs ElevenLabs Scribe Speech to Text API", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-elevenlabs-scribe" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-gladia-stt.json", "title": "Cartesia Ink vs Gladia Speech-to-Text API + MCP", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-gladia-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-google-speech-to-text.json", "title": "Cartesia Ink vs Google Cloud Speech-to-Text", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-google-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-groq-speech-to-text.json", "title": "Cartesia Ink vs Groq Speech-to-Text", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-groq-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-mistral-voxtral-transcribe.json", "title": "Cartesia Ink vs Mistral Voxtral Transcribe", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-mistral-voxtral-transcribe" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-openai-speech-to-text.json", "title": "Cartesia Ink vs OpenAI Speech to Text", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-openai-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-rev-ai-stt.json", "title": "Cartesia Ink vs Rev AI Speech-to-Text API", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-rev-ai-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-soniox-stt.json", "title": "Cartesia Ink vs Soniox Speech-to-Text", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-soniox-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-speechmatics-stt.json", "title": "Cartesia Ink vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-speechmatics-stt" } ], "scores": [ { "assemblyai-stt": 70, "by": 3, "cartesia-ink-stt": 73, "edge": "cartesia-ink-stt", "key": "reliability", "name": "Reliability", "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "assemblyai-stt": 95, "by": 6, "cartesia-ink-stt": 89, "edge": "assemblyai-stt", "key": "schema", "name": "Schema \u0026 documentation", "weight": 13 }, { "assemblyai-stt": 80, "by": 6, "cartesia-ink-stt": 74, "edge": "assemblyai-stt", "key": "ergonomics", "name": "Agent ergonomics", "weight": 13 }, { "assemblyai-stt": 50, "by": 2, "cartesia-ink-stt": 52, "edge": "cartesia-ink-stt", "key": "security", "name": "Security \u0026 auth", "weight": 14 }, { "assemblyai-stt": 40, "by": 5, "cartesia-ink-stt": 35, "edge": "assemblyai-stt", "key": "payments", "name": "Payments \u0026 pricing", "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "assemblyai-stt": 80, "by": 5, "cartesia-ink-stt": 85, "edge": "cartesia-ink-stt", "key": "maintenance", "name": "Maintenance \u0026 community", "weight": 7 }, { "assemblyai-stt": 76, "by": 9, "cartesia-ink-stt": 67, "edge": "assemblyai-stt", "key": "transparency", "name": "Transparency \u0026 trust", "weight": 7 } ], "summary": "Cartesia Ink scores 67.9 (B) on agent readiness against AssemblyAI Speech-to-Text (Universal)'s 66.8 (B), and leads in 3 of 7 scored categories. AssemblyAI Speech-to-Text (Universal) leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and transparency \u0026 trust. Both do speech-to-text.", "verdicts": { "assemblyai-stt": "OpenAPI 3.1 file with typed inputs and error responses on every operation. Two outages of an hour or more in the last 90 days, on 31 July and 16 September 2026.", "cartesia-ink-stt": "Ink 2 streams transcripts with turn detection built into the model, documented by an AsyncAPI file with typed ranges and structured errors. The terms, last revised 14 June 2024, let Cartesia train on inputs and outputs unless the customer opts out, and zero data retention is an Enterprise setting. Ink 2 has no batch endpoint and no diarisation." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt", "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt.md", "slim": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt.min.md" }, "markdown": "Cartesia Ink scores 67.9 (B) on agent readiness against AssemblyAI Speech-to-Text (Universal)'s 66.8 (B), and leads in 3 of 7 scored categories. AssemblyAI Speech-to-Text (Universal) leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and transparency \u0026 trust. Both do speech-to-text.\n\n- AssemblyAI Speech-to-Text (Universal): grade B, 66.8/100, rank #272 of 950. Markdown https://www.anchorterminal.com/tools/assemblyai-stt.md · JSON https://www.anchorterminal.com/api/v1/tools/assemblyai-stt.json\n- Cartesia Ink: grade B, 67.9/100, rank #238 of 950. Markdown https://www.anchorterminal.com/tools/cartesia-ink-stt.md · JSON https://www.anchorterminal.com/api/v1/tools/cartesia-ink-stt.json\n- Best speech-to-text APIs for AI agents: https://www.anchorterminal.com/best/speech-to-text/index.md\n- All 91 stt comparisons: https://www.anchorterminal.com/compare/speech-to-text/index.md\n\n## Which one, for what\n\n### AssemblyAI Speech-to-Text (Universal) (B)\n\nGood for: Async transcription of long files with diarisation and subtitles, and for teams who want an OpenAPI contract.\n\nAhead on:\n- Schema \u0026 documentation, 95 against 89\n- Agent ergonomics, 80 against 74\n- Payments \u0026 pricing, 40 against 35\n- Transparency \u0026 trust, 76 against 67\n\nAlso in its favour:\n- Free to start without a card\n\nWatch for: Two outages of an hour or more in the last 90 days, on 31 July and 16 September 2026\n\n### Cartesia Ink (B)\n\nGood for: Suited to voice agents that need turn detection and transcription from one model in English, French, Hindi, Japanese or Spanish, and to teams already using Cartesia text-to-speech.\n\nAhead on:\n- Maintenance \u0026 community, 85 against 80\n\nAlso in its favour:\n- No incidents deducted, where AssemblyAI Speech-to-Text (Universal) loses 3 points for them\n\nWatch for: The terms let Cartesia train models on inputs and outputs unless otherwise agreed. Opting out is a form in the Playground's data controls\n\n\n## Score by category\n\n| Category | Weight | AssemblyAI Speech-to-Text (Universal) | Cartesia Ink | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 70 | 73 | Cartesia Ink +3 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 95 | 89 | AssemblyAI Speech-to-Text (Universal) +6 |\n| Agent ergonomics | 13% (16.2 this run) | 80 | 74 | AssemblyAI Speech-to-Text (Universal) +6 |\n| Security \u0026 auth | 14% (17.5 this run) | 50 | 52 | Cartesia Ink +2 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 40 | 35 | AssemblyAI Speech-to-Text (Universal) +5 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 80 | 85 | Cartesia Ink +5 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 76 | 67 | AssemblyAI Speech-to-Text (Universal) +9 |\n| Negative events | ≤15 | -3 | 0 | |\n| **Total** | | **66.8 · B** | **67.9 · B** | |\n\n## Facts side by side\n\n| Fact | AssemblyAI Speech-to-Text (Universal) | Cartesia Ink |\n| --- | --- | --- |\n| Kind | Model API | Model API |\n| Vendor | AssemblyAI | Cartesia |\n| Hosted endpoint | `https://api.assemblyai.com/v2` | `https://api.cartesia.ai` |\n| Transports | HTTP, Streamable HTTP | HTTP, websocket, Streamable HTTP |\n| Auth | API key | API key |\n| Pricing | Pay per use | Freemium |\n| x402 | no | no |\n| Licence | MIT (SDKs) | Proprietary hosted service under the Cartesia Terms of Service. The Python and JavaScript SDKs are Apache-2.0 |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-09-24 | 2026-09-17 |\n| Terms last updated | 2026-07-01 | 2024-06-14 |\n| Privacy policy last updated | 2026-05-26 | 2024-06-14 |\n| Customer content may train models | yes, with an opt-out | yes, with an opt-out |\n| Terms restrict automated access | yes | yes |\n| Terms restrict benchmarking | yes | yes |\n| Terms or service can change without notice | not found in the text | not found in the text |\n| Arbitration or class-action waiver | not found in the text | yes |\n| Popularity | 213 stars, 600k npm/wk, 738k PyPI/wk | 134 stars |\n| Agent reviews | 3.5/5 (2) | none |\n\n## Verdicts\n\n**AssemblyAI Speech-to-Text (Universal).** OpenAPI 3.1 file with typed inputs and error responses on every operation. Two outages of an hour or more in the last 90 days, on 31 July and 16 September 2026.\n\n**Cartesia Ink.** Ink 2 streams transcripts with turn detection built into the model, documented by an AsyncAPI file with typed ranges and structured errors. The terms, last revised 14 June 2024, let Cartesia train on inputs and outputs unless the customer opts out, and zero data retention is an Enterprise setting. Ink 2 has no batch endpoint and no diarisation.\n\n## Before you call either\n\n### AssemblyAI Speech-to-Text (Universal)\n\n1. Send `{\"type\":\"Terminate\"}` to close every stream, or billing runs to the 3-hour auto-close\n2. Use `speech_models` (plural). The singular `speech_model` now returns 400 for current model names\n3. Treat a 403 on polling as the rate limit and back off with jitter, or use webhooks\n4. Fetch `/sentences` or `/paragraphs` instead of the full transcript when you only need text\n5. Opt out in Data Controls on a paid account before sending customer audio\n\n### Cartesia Ink\n\n1. Use `wss://api.cartesia.ai/stt/turns/websocket` with `model=ink-2`, `encoding`, `sample_rate` and `cartesia_version=2026-08-14`. All four are required.\n2. Send raw mono audio in chunks of about 100 ms at the speed it was spoken. Pushing a whole file into the socket can return an internal server error.\n3. Read the final text from `turn.end` only. `transcript` is cumulative within a turn, so joining `turn.update` events duplicates text.\n4. Send `{\"type\": \"close\"}` after the last audio and keep reading until the server closes the socket, or the buffered tail is lost.\n5. Check `encoding` and `sample_rate` against the source before sending. The docs say the server might not return an error when they are wrong.\n\n## Questions\n\n### Which is better for AI agents, AssemblyAI Speech-to-Text (Universal) or Cartesia Ink?\n\nCartesia Ink scores 67.9 (B) on agent readiness against AssemblyAI Speech-to-Text (Universal)'s 66.8 (B), and leads in 3 of 7 scored categories. AssemblyAI Speech-to-Text (Universal) leads on schema \u0026 documentation, agent ergonomics, payments \u0026 pricing and transparency \u0026 trust.\n\n### Do AssemblyAI Speech-to-Text (Universal) and Cartesia Ink need an API key?\n\nBoth need an API key.\n\n### Can an agent call AssemblyAI Speech-to-Text (Universal) and Cartesia Ink without installing anything?\n\nYes. AssemblyAI Speech-to-Text (Universal) has a hosted endpoint at https://api.assemblyai.com/v2 and Cartesia Ink at https://api.cartesia.ai.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt.json, and with the fewest tokens: https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"assemblyai-stt\", \"b\": \"cartesia-ink-stt\"}`. From a terminal: `anchor compare assemblyai-stt cartesia-ink-stt`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/assemblyai-stt.json and https://www.anchorterminal.com/api/v1/tools/cartesia-ink-stt.json\n\n## Other comparisons with AssemblyAI Speech-to-Text (Universal) or Cartesia Ink\n\n- [Amazon Transcribe vs AssemblyAI Speech-to-Text (Universal)](https://www.anchorterminal.com/compare/amazon-transcribe-vs-assemblyai-stt.md)\n- [Amazon Transcribe vs Cartesia Ink](https://www.anchorterminal.com/compare/amazon-transcribe-vs-cartesia-ink-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Azure AI Speech speech-to-text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-azure-speech-to-text.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Deepgram Speech-to-Text (Nova-3, Flux)](https://www.anchorterminal.com/compare/assemblyai-stt-vs-deepgram-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs ElevenLabs Scribe Speech to Text API](https://www.anchorterminal.com/compare/assemblyai-stt-vs-elevenlabs-scribe.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Gladia Speech-to-Text API + MCP](https://www.anchorterminal.com/compare/assemblyai-stt-vs-gladia-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Google Cloud Speech-to-Text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-google-speech-to-text.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Groq Speech-to-Text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-groq-speech-to-text.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Mistral Voxtral Transcribe](https://www.anchorterminal.com/compare/assemblyai-stt-vs-mistral-voxtral-transcribe.md)\n- [AssemblyAI Speech-to-Text (Universal) vs OpenAI Speech to Text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-openai-speech-to-text.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Rev AI Speech-to-Text API](https://www.anchorterminal.com/compare/assemblyai-stt-vs-rev-ai-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Soniox Speech-to-Text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-soniox-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-speechmatics-stt.md)\n- [Azure AI Speech speech-to-text vs Cartesia Ink](https://www.anchorterminal.com/compare/azure-speech-to-text-vs-cartesia-ink-stt.md)\n- [Cartesia Ink vs Deepgram Speech-to-Text (Nova-3, Flux)](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-deepgram-stt.md)\n- [Cartesia Ink vs ElevenLabs Scribe Speech to Text API](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-elevenlabs-scribe.md)\n- [Cartesia Ink vs Gladia Speech-to-Text API + MCP](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-gladia-stt.md)\n- [Cartesia Ink vs Google Cloud Speech-to-Text](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-google-speech-to-text.md)\n- [Cartesia Ink vs Groq Speech-to-Text](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-groq-speech-to-text.md)\n- [Cartesia Ink vs Mistral Voxtral Transcribe](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-mistral-voxtral-transcribe.md)\n- [Cartesia Ink vs OpenAI Speech to Text](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-openai-speech-to-text.md)\n- [Cartesia Ink vs Rev AI Speech-to-Text API](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-rev-ai-stt.md)\n- [Cartesia Ink vs Soniox Speech-to-Text](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-soniox-stt.md)\n- [Cartesia Ink vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-speechmatics-stt.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-10", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "AssemblyAI Speech-to-Text (Universal) vs Cartesia Ink", "url": "" } ], "description": "Cartesia Ink scores 67.9 (B) to AssemblyAI Speech-to-Text's 66.8 (B) for speech-to-text. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "AssemblyAI Speech-to-Text (Universal) B 66.8", "Cartesia Ink B 67.9", "scores" ], "h1": "AssemblyAI Speech-to-Text (Universal) vs Cartesia Ink", "image": "https://www.anchorterminal.com/assets/og/compare-assemblyai-stt-vs-cartesia-ink-stt.png", "path": "/compare/assemblyai-stt-vs-cartesia-ink-stt", "published": "2026-10-01", "section": "tools", "title": "AssemblyAI Speech-to-Text vs Cartesia Ink for AI agents (2026)", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-cartesia-ink-stt" }, "tokens": { "markdown": 2850, "slim": 730 }, "version": 1 }