{ "data": { "a": { "slug": "cartesia-tts", "name": "Cartesia Sonic TTS API + MCP", "vendor": "Cartesia", "vendorUrl": "https://cartesia.ai", "kind": "model", "category": "text-to-speech", "summary": "Sonic text-to-speech, currently `sonic-3.6` in 44 languages, over `/tts/bytes`, `/tts/sse` and a WebSocket that takes streamed LLM text with contexts and word timestamps.", "url": "https://www.anchorterminal.com/tools/cartesia-tts", "markdownUrl": "https://www.anchorterminal.com/tools/cartesia-tts.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/cartesia-tts.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/cartesia-tts.json", "repo": "https://github.com/cartesia-ai/cartesia-python", "license": "Apache-2.0 (SDKs)", "transports": [ "http", "streamable-http", "stdio" ], "remoteUrl": "https://api.cartesia.ai", "packages": [ { "registry": "npm", "name": "@cartesia/cartesia-js" }, { "registry": "pypi", "name": "cartesia" }, { "registry": "pypi", "name": "cartesia-mcp" } ], "auth": "mixed", "authNotes": "`Authorization: Bearer` API key plus a required `Cartesia-Version` date header (currently `2026-08-14`). Browsers should use short-lived access tokens minted server-side. The hosted MCP at `https://mcp.cartesia.ai/mcp` signs in through the Playground and creates an MCP key. The local `cartesia-mcp` reads `CARTESIA_API_KEY`.", "pricing": "freemium", "pricingNotes": "TTS costs about 1 credit a character, charged only on successful requests. Free has 20,000 credits a month (about 27 minutes of Sonic 3.6), Pro $5 100,000, Startup $49 1.25M and Scale $299 8M. Overages, if enabled, cost $65 per 1M credits on Pro, $45 on Startup and $38 on Scale. Commercial use starts at Pro. Unused credits roll over up to 2 times the monthly amount (https://cartesia.ai/pricing).", "priceSummary": "$5 / mo", "where": "both", "x402": { "level": "no", "evidence": "No x402 or machine payment in the docs or pricing (checked 2026-09-30).", "endpoints": [] }, "toolCount": 15, "popularity": { "githubStars": 133, "npmWeekly": 166023, "pypiWeekly": 176771, "asOf": "2026-09-30" }, "docsUrl": "https://docs.cartesia.ai/build-with-cartesia/tts-models/latest", "llmsTxt": "https://docs.cartesia.ai/llms.txt", "capabilities": [ "speech.tts", "speech.streaming", "speech.voices", "speech.ssml", "speech.languages" ], "tags": [ "hosted", "freemium", "free-tier", "closed-source", "python", "typescript", "llms-txt", "mcp", "streaming", "enterprise" ], "lastRelease": "2026-09-30", "graded": true, "anchor": { "graded": true, "score": 64.2, "grade": "B", "agentReady": false, "rank": 187, "ranked": true, "rankOf": 452, "categoryRank": 6, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 65, "maintenance": 79, "payments": 30, "reliability": 63, "schema": 86, "security": 58, "transparency": 71 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "WebSocket input accepts streamed LLM text with contexts, flushing and word timestamps. Five TTS incidents on the status page between 29 July and 21 August 2026.", "strengths": [ "WebSocket input accepts streamed LLM text with contexts, flushing and word timestamps", "Dated model snapshots such as `sonic-3.6-2026-08-27` never change, and `Cartesia-Version` pins the API shape", "OpenAPI and AsyncAPI files per API version listed in llms.txt", "Short-lived access tokens with TTS, STT and agent grants for browser clients", "Deprecations dated in the changelog, Sonic-2 and Sonic Turbo sunset after 2026-10-20" ], "weaknesses": [ "Five TTS incidents on the status page between 29 July and 21 August 2026", "TTS concurrency is 2 on Free, 3 on Pro, 5 on Startup and 15 on Scale", "The Terms allow training on inputs and outputs unless you opt out by form", "Zero data retention is Enterprise only", "No SLA, and no error responses documented for the TTS endpoints" ], "agentNotes": [ "Send the `Cartesia-Version` header on every request.", "Pin a dated snapshot such as `sonic-3.6-2026-08-27` if output must not change.", "Move off `sonic-2`, `sonic-turbo` and `sonic-3-2025-10-27` before 2026-10-20.", "Expect a 429 at the plan's concurrency limit and queue requests yourself.", "Mint a short-lived access token for browser clients instead of shipping the API key." ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 64.2 } ], "editorialScores": { "ergonomics": 65, "maintenance": 79, "payments": 30, "reliability": 63, "schema": 86, "security": 58, "transparency": 60 }, "provenanceScore": 82 }, "connect": { "http": "curl -X POST https://api.cartesia.ai/tts/bytes -H \"Authorization: Bearer $CARTESIA_API_KEY\" \\\n -H \"Cartesia-Version: 2026-08-14\" -H \"content-type: application/json\" -o speech.wav \\\n -d '{\"model_id\":\"sonic-3.6\",\"transcript\":\"Your table is booked for seven.\",\"voice\":{\"id\":\"47c38ca4-5f35-497b-b1a3-415245fb35e1\"},\"output_format\":{\"container\":\"wav\",\"encoding\":\"pcm_s16le\",\"sample_rate\":44100}}'", "claudeCode": "claude mcp add --transport http --scope user cartesia https://mcp.cartesia.ai/mcp", "config": { "mcpServers": { "cartesia": { "args": [ "cartesia-mcp" ], "command": "uvx", "env": { "CARTESIA_API_KEY": "${CARTESIA_API_KEY}" } } } } }, "letme": { "capability": "https://letme.dev/speech.tts", "tool": "https://letme.dev/cartesia-tts" }, "sameCompany": [ "cartesia-voice-cloning" ], "area": "voice", "unitPrices": [ { "item": "Sonic TTS overage on Pro", "unit": "1m-chars", "usd": 65, "note": "about 1 credit a character, $65 per 1M credits" }, { "item": "Sonic TTS overage on Startup", "unit": "1m-chars", "usd": 45 }, { "item": "Sonic TTS overage on Scale", "unit": "1m-chars", "usd": 38 }, { "item": "Pro plan", "unit": "month", "usd": 5, "note": "100,000 credits" }, { "item": "Startup plan", "unit": "month", "usd": 49, "note": "1.25M credits" }, { "item": "Scale plan", "unit": "month", "usd": 299, "note": "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": "none", "checked": "2026-09-30", "score": 82 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/cartesia-tts.json", "live": { "slug": "cartesia-tts", "probe": { "target": "https://api.cartesia.ai", "method": "get", "lastAt": "2026-10-05T00:25:40.801190313Z", "lastOk": true, "lastStatus": 200, "lastMs": 92, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 61, "p95ms24h": 137, "samples24h": 272, "samples30d": 1107, "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": 5, "ok": 5 } ] }, "vendorStatus": { "page": "https://status.cartesia.ai", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-05T00:22:38.61205555Z" }, "versions": [ { "registry": "github", "name": "cartesia-ai/cartesia-python", "version": "v4.2.0", "released": "2026-09-02", "seenAt": "2026-10-04T16:23:11.882857509Z" }, { "registry": "npm", "name": "@cartesia/cartesia-js", "version": "4.2.0", "seenAt": "2026-10-04T16:23:08.936594762Z" }, { "registry": "pypi", "name": "cartesia", "version": "4.2.0", "released": "2026-09-02", "seenAt": "2026-10-04T16:23:09.798087978Z" }, { "registry": "pypi", "name": "cartesia-mcp", "version": "0.26.0", "released": "2026-09-30", "seenAt": "2026-10-04T16:23:09.984461576Z" } ], "githubStars": 133, "npmWeekly": 108942, "pypiWeekly": 188249, "securityTxt": { "url": "https://cartesia.ai/.well-known/security.txt", "state": "valid", "expires": "2027-10-03T00:00:00.000Z", "checkedAt": "2026-10-04T15:15:57.920556028Z" }, "llmsTxt": { "url": "https://docs.cartesia.ai/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:17:23.748277625Z" }, "domain": { "domain": "cartesia.ai", "registered": "2023-05-10", "source": "https://rdap.identitydigital.services/rdap/domain/cartesia.ai", "checkedAt": "2026-10-04T13:04:05.26596839Z" }, "pages": [ { "url": "https://docs.cartesia.ai/changelog/2026", "kind": "changelog", "status": 200, "checkedAt": "2026-10-04T15:43:22.154553148Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "56a07dda1f5d" }, { "url": "https://cartesia.ai/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-04T15:41:44.64571005Z", "changedAt": "2026-10-03T15:29:56.901063562Z", "fingerprint": "3e49bcd49fcf" }, { "url": "https://www.cartesia.ai/legal/privacy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-04T15:49:41.751185158Z", "changedAt": "2026-10-03T15:37:37.717663201Z", "fingerprint": "6fea00c7255f" }, { "url": "https://www.cartesia.ai/legal/terms", "kind": "terms", "status": 200, "checkedAt": "2026-10-04T15:49:43.846741137Z", "changedAt": "2026-10-03T15:37:39.779484537Z", "fingerprint": "c899e30661ba" } ], "updatedAt": "2026-10-05T00:25:40.801190313Z" } }, "b": { "slug": "deepgram-tts", "name": "Deepgram Text-to-Speech (Aura-2, Flux TTS)", "vendor": "Deepgram", "vendorUrl": "https://deepgram.com", "kind": "model", "category": "text-to-speech", "summary": "Deepgram's text-to-speech API for generating spoken audio.", "url": "https://www.anchorterminal.com/tools/deepgram-tts", "markdownUrl": "https://www.anchorterminal.com/tools/deepgram-tts.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/deepgram-tts.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/deepgram-tts.json", "repo": "https://github.com/deepgram/deepgram-python-sdk", "license": "MIT (SDKs)", "transports": [ "http", "streamable-http", "stdio", "sse" ], "remoteUrl": "https://api.deepgram.com/v1", "packages": [ { "registry": "npm", "name": "@deepgram/sdk" }, { "registry": "pypi", "name": "deepgram-sdk" }, { "registry": "pypi", "name": "deepctl" } ], "auth": "api-key", "authNotes": "`Authorization: Token \u003ckey\u003e` header on REST and WebSocket calls. Short-lived JWTs (30-second TTL) from the token endpoint for browsers. The `dg` CLI MCP server uses `dg login` credentials or `DEEPGRAM_API_KEY`. The docs MCP needs no key.", "pricing": "usage", "pricingNotes": "$200 free credit with no card, then pay as you go. Flux TTS $0.045 per 1,000 characters, Aura-2 $0.030, Aura-1 $0.015. Growth (from $4,000 a year prepaid) cuts these to $0.0405, $0.027 and $0.0135. A matching-credit offer on Flux TTS runs to 2026-12-31, capped at $500 (https://deepgram.com/pricing).", "priceSummary": "Pay per use", "where": "both", "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": 468, "npmWeekly": 1123798, "pypiWeekly": 805026, "asOf": "2026-09-30" }, "docsUrl": "https://developers.deepgram.com/docs/tts-models-languages-overview", "llmsTxt": "https://developers.deepgram.com/llms.txt", "openapi": "https://developers.deepgram.com/openapi.json", "capabilities": [ "speech.tts", "speech.streaming", "speech.voices", "speech.languages" ], "tags": [ "hosted", "no-card", "closed-source", "python", "typescript", "openapi", "llms-txt", "mcp", "streaming", "batch", "enterprise", "self-hosted" ], "lastRelease": "2026-09-29", "graded": true, "anchor": { "graded": true, "score": 73, "grade": "BB", "agentReady": true, "rank": 63, "ranked": true, "rankOf": 452, "categoryRank": 4, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 82, "maintenance": 73, "payments": 40, "reliability": 70, "schema": 95, "security": 70, "transparency": 75 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "high", "date": "2026-10-01" }, "negative": 0, "verdict": "OpenAPI 3.1 and AsyncAPI files, llms.txt and Markdown pages. Requests can be kept for training unless each one sets `mip_opt_out=true`.", "strengths": [ "OpenAPI 3.1 and AsyncAPI files, llms.txt and Markdown pages", "Flux TTS's Interrupt event returns `text_spoken` and `text_remaining` on barge-in", "Keys carry roles and scopes, and browser tokens live 30 seconds", "Per-request logs through `GET /v1/projects/{project_id}/requests`, filterable by date and status", "$200 credit with no card, then Aura-2 at $0.030 per 1,000 characters" ], "weaknesses": [ "Requests can be kept for training unless each one sets `mip_opt_out=true`", "Flux TTS is English only and capped at 5 concurrent streams in the EU, Australia and India below Enterprise", "No SSML, and Flux TTS strips other vendors' tags with a warning", "Elevated Flux TTS errors for about four hours on 25 September 2026", "Aura-2 REST requests stop at 2,000 characters" ], "agentNotes": [ "Set `mip_opt_out=true` on every request if the text mustn't be kept for training.", "Split Aura-2 REST text under 2,000 characters or expect a 413.", "Pass `model` on `/v2/speak`, where it's required.", "Strip SSML before sending, since it's removed with an `INPUT_MARKUP_STRIPPED` warning.", "Back off exponentially on 429 and keep traffic in one project." ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3.5, "history": [ { "basis": "public evidence", "confidence": "high", "grade": "BB", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 73 } ], "editorialScores": { "ergonomics": 82, "maintenance": 73, "payments": 40, "reliability": 70, "schema": 95, "security": 70, "transparency": 60 }, "provenanceScore": 90 }, "connect": { "http": "curl \"https://api.deepgram.com/v1/speak?model=aura-2-thalia-en\" \\\n -H \"Authorization: Token $DEEPGRAM_API_KEY\" -H \"content-type: application/json\" \\\n -d '{\"text\":\"Hello, how are you?\"}' -o hello.mp3", "claudeCode": "claude mcp add deepgram-docs --transport http https://api.dx.deepgram.com/kapa/mcp", "config": { "mcpServers": { "deepgram": { "args": [ "mcp" ], "command": "dg", "env": { "DEEPGRAM_API_KEY": "${DEEPGRAM_API_KEY}" } } } } }, "letme": { "capability": "https://letme.dev/speech.tts", "tool": "https://letme.dev/deepgram-tts" }, "sameCompany": [ "deepgram-stt", "deepgram-voice-agent" ], "area": "voice", "unitPrices": [ { "item": "Flux TTS", "unit": "1m-chars", "usd": 45, "note": "pay as you go, $0.045 per 1,000 characters" }, { "item": "Aura-2", "unit": "1m-chars", "usd": 30, "note": "pay as you go" }, { "item": "Aura-1", "unit": "1m-chars", "usd": 15, "note": "pay as you go" }, { "item": "Aura-2 on Growth", "unit": "1m-chars", "usd": 27, "note": "prepaid annual plan from $4,000" } ], "provenance": { "legalEntity": "Deepgram, Inc.", "domain": "deepgram.com", "domainRegistered": "2016-01-28", "endpointOnVendorDomain": true, "terms": "https://deepgram.com/terms", "privacy": "https://deepgram.com/privacy", "statusPage": "https://status.deepgram.com", "changelog": "https://developers.deepgram.com/changelog", "securityTxt": "none", "checked": "2026-09-30", "score": 90 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/deepgram-tts.json", "live": { "slug": "deepgram-tts", "probe": { "target": "https://api.deepgram.com/v1", "method": "get", "lastAt": "2026-10-05T00:25:41.847839418Z", "lastOk": true, "lastStatus": 404, "lastMs": 335, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 347, "p95ms24h": 521, "samples24h": 272, "samples30d": 1107, "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": 5, "ok": 5 } ] }, "vendorStatus": { "page": "https://status.deepgram.com", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-05T00:22:41.65676275Z" }, "versions": [ { "registry": "github", "name": "deepgram/deepgram-python-sdk", "version": "v7.12.0", "released": "2026-10-02", "seenAt": "2026-10-04T16:25:18.900755205Z" }, { "registry": "npm", "name": "@deepgram/sdk", "version": "5.14.0", "seenAt": "2026-10-04T16:25:16.604084571Z" }, { "registry": "pypi", "name": "deepctl", "version": "0.3.1", "released": "2026-09-29", "seenAt": "2026-10-04T16:25:17.004312351Z" }, { "registry": "pypi", "name": "deepgram-sdk", "version": "7.12.0", "released": "2026-10-02", "seenAt": "2026-10-04T16:25:16.891210762Z" } ], "githubStars": 468, "npmWeekly": 1147181, "pypiWeekly": 806541, "securityTxt": { "url": "https://deepgram.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:16:00.338324598Z" }, "llmsTxt": { "url": "https://developers.deepgram.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:17:31.890004033Z" }, "domain": { "domain": "deepgram.com", "registered": "2016-01-28", "source": "https://rdap.verisign.com/com/v1/domain/deepgram.com", "checkedAt": "2026-10-04T13:03:28.939824686Z" }, "updatedAt": "2026-10-05T00:25:41.847839418Z" } }, "summary": "Deepgram Text-to-Speech (Aura-2, Flux TTS) has a score of 73 (BB) against Cartesia Sonic TTS API + MCP's 64.2 (B). Both do speech tts. The largest gap is agent ergonomics, 17 points." }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/cartesia-tts-vs-deepgram-tts", "json": "https://www.anchorterminal.com/compare/cartesia-tts-vs-deepgram-tts.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/cartesia-tts-vs-deepgram-tts.md", "slim": "https://www.anchorterminal.com/compare/cartesia-tts-vs-deepgram-tts.min.md" }, "markdown": "Deepgram Text-to-Speech (Aura-2, Flux TTS) has a score of 73 (BB) against Cartesia Sonic TTS API + MCP's 64.2 (B). Both do speech tts. The largest gap is agent ergonomics, 17 points.\n\n- Cartesia Sonic TTS API + MCP: grade B, 64.2/100, rank #187 of 452. Markdown https://www.anchorterminal.com/tools/cartesia-tts.md · JSON https://www.anchorterminal.com/api/v1/tools/cartesia-tts.json\n- Deepgram Text-to-Speech (Aura-2, Flux TTS): grade BB, 73/100, rank #63 of 452. Markdown https://www.anchorterminal.com/tools/deepgram-tts.md · JSON https://www.anchorterminal.com/api/v1/tools/deepgram-tts.json\n\n## Which one, for what\n\nPick Cartesia Sonic TTS API + MCP for maintenance \u0026 community (+6).\n\nPick Deepgram Text-to-Speech (Aura-2, Flux TTS) for reliability (+7), schema \u0026 documentation (+9), agent ergonomics (+17), security \u0026 auth (+12), payments \u0026 pricing (+10).\n\n## Score by category\n\n| Category | Weight | Cartesia Sonic TTS API + MCP | Deepgram Text-to-Speech (Aura-2, Flux TTS) | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 63 | 70 | Deepgram Text-to-Speech (Aura-2, Flux TTS) +7 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 86 | 95 | Deepgram Text-to-Speech (Aura-2, Flux TTS) +9 |\n| Agent ergonomics | 13% (16.2 this run) | 65 | 82 | Deepgram Text-to-Speech (Aura-2, Flux TTS) +17 |\n| Security \u0026 auth | 14% (17.5 this run) | 58 | 70 | Deepgram Text-to-Speech (Aura-2, Flux TTS) +12 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 30 | 40 | Deepgram Text-to-Speech (Aura-2, Flux TTS) +10 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 79 | 73 | Cartesia Sonic TTS API + MCP +6 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 71 | 75 | Deepgram Text-to-Speech (Aura-2, Flux TTS) +4 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **64.2 · B** | **73 · BB** | |\n\n## Facts side by side\n\n| Fact | Cartesia Sonic TTS API + MCP | Deepgram Text-to-Speech (Aura-2, Flux TTS) |\n| --- | --- | --- |\n| Kind | Model API | Model API |\n| Vendor | Cartesia | Deepgram |\n| Hosted endpoint | `https://api.cartesia.ai` | `https://api.deepgram.com/v1` |\n| Transports | HTTP, Streamable HTTP, stdio | HTTP, Streamable HTTP, stdio, SSE (legacy) |\n| Auth | OAuth or key | API key |\n| Pricing | Freemium | Pay per use |\n| x402 | no | no |\n| Licence | Apache-2.0 (SDKs) | MIT (SDKs) |\n| Tools exposed | 15 | none |\n| Context cost (tools/list) | n/a | n/a |\n| p95 latency | not measured yet | not measured yet |\n| Availability (30d) | not measured yet | not measured yet |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| MCP registry | not listed | not listed |\n| Last release | 2026-09-30 | 2026-09-29 |\n| Popularity | 133 stars, 166k npm/wk, 177k PyPI/wk | 468 stars, 1.1M npm/wk, 805k PyPI/wk |\n| Agent reviews | 3/5 (2) | 3.5/5 (2) |\n\n## Verdicts\n\n**Cartesia Sonic TTS API + MCP.** WebSocket input accepts streamed LLM text with contexts, flushing and word timestamps. Five TTS incidents on the status page between 29 July and 21 August 2026.\n\n**Deepgram Text-to-Speech (Aura-2, Flux TTS).** OpenAPI 3.1 and AsyncAPI files, llms.txt and Markdown pages. Requests can be kept for training unless each one sets `mip_opt_out=true`.\n\n## Before you call either\n\n### Cartesia Sonic TTS API + MCP\n\n1. Send the `Cartesia-Version` header on every request.\n2. Pin a dated snapshot such as `sonic-3.6-2026-08-27` if output must not change.\n3. Move off `sonic-2`, `sonic-turbo` and `sonic-3-2025-10-27` before 2026-10-20.\n4. Expect a 429 at the plan's concurrency limit and queue requests yourself.\n5. Mint a short-lived access token for browser clients instead of shipping the API key.\n\n### Deepgram Text-to-Speech (Aura-2, Flux TTS)\n\n1. Set `mip_opt_out=true` on every request if the text mustn't be kept for training.\n2. Split Aura-2 REST text under 2,000 characters or expect a 413.\n3. Pass `model` on `/v2/speak`, where it's required.\n4. Strip SSML before sending, since it's removed with an `INPUT_MARKUP_STRIPPED` warning.\n5. Back off exponentially on 429 and keep traffic in one project.\n\n## Other comparisons with Cartesia Sonic TTS API + MCP or Deepgram Text-to-Speech (Aura-2, Flux TTS)\n\n- [Amazon Polly vs Cartesia Sonic TTS API + MCP](https://www.anchorterminal.com/compare/amazon-polly-vs-cartesia-tts.md)\n- [Amazon Polly vs Deepgram Text-to-Speech (Aura-2, Flux TTS)](https://www.anchorterminal.com/compare/amazon-polly-vs-deepgram-tts.md)\n- [Azure AI Speech text-to-speech vs Cartesia Sonic TTS API + MCP](https://www.anchorterminal.com/compare/azure-text-to-speech-vs-cartesia-tts.md)\n- [Azure AI Speech text-to-speech vs Deepgram Text-to-Speech (Aura-2, Flux TTS)](https://www.anchorterminal.com/compare/azure-text-to-speech-vs-deepgram-tts.md)\n- [Cartesia Sonic TTS API + MCP vs ElevenLabs Text to Speech API + MCP](https://www.anchorterminal.com/compare/cartesia-tts-vs-elevenlabs-tts.md)\n- [Cartesia Sonic TTS API + MCP vs Murf TTS API + MCP](https://www.anchorterminal.com/compare/cartesia-tts-vs-murf-tts.md)\n- [Cartesia Sonic TTS API + MCP vs PlayHT Text-to-Speech API](https://www.anchorterminal.com/compare/cartesia-tts-vs-playht-tts.md)\n- [Cartesia Sonic TTS API + MCP vs Resemble AI Text-to-Speech API](https://www.anchorterminal.com/compare/cartesia-tts-vs-resemble-ai-tts.md)\n- [Cartesia Sonic TTS API + MCP vs Rime TTS API + MCP](https://www.anchorterminal.com/compare/cartesia-tts-vs-rime-tts.md)\n- [Cartesia Sonic TTS API + MCP vs Soniox Text-to-Speech](https://www.anchorterminal.com/compare/cartesia-tts-vs-soniox-tts.md)\n- [Deepgram Text-to-Speech (Aura-2, Flux TTS) vs ElevenLabs Text to Speech API + MCP](https://www.anchorterminal.com/compare/deepgram-tts-vs-elevenlabs-tts.md)\n- [Deepgram Text-to-Speech (Aura-2, Flux TTS) vs Murf TTS API + MCP](https://www.anchorterminal.com/compare/deepgram-tts-vs-murf-tts.md)\n- [Deepgram Text-to-Speech (Aura-2, Flux TTS) vs PlayHT Text-to-Speech API](https://www.anchorterminal.com/compare/deepgram-tts-vs-playht-tts.md)\n- [Deepgram Text-to-Speech (Aura-2, Flux TTS) vs Resemble AI Text-to-Speech API](https://www.anchorterminal.com/compare/deepgram-tts-vs-resemble-ai-tts.md)\n- [Deepgram Text-to-Speech (Aura-2, Flux TTS) vs Rime TTS API + MCP](https://www.anchorterminal.com/compare/deepgram-tts-vs-rime-tts.md)\n- [Deepgram Text-to-Speech (Aura-2, Flux TTS) vs Soniox Text-to-Speech](https://www.anchorterminal.com/compare/deepgram-tts-vs-soniox-tts.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-05", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.3", "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": "Cartesia Sonic TTS API + MCP vs Deepgram Text-to-Speech (Aura-2, Flux TTS)", "url": "" } ], "description": "Deepgram Text-to-Speech (Aura-2, Flux TTS) has a score of 73 (BB) against Cartesia Sonic TTS API + MCP's 64.2 (B). Both do speech tts. The largest gap is agent ergonomics, 17 points. Category scores, facts, verdicts and agent notes side by side.", "facts": [ "Cartesia Sonic TTS API + MCP B 64.2", "Deepgram Text-to-Speech (Aura-2, Flux TTS) BB 73", "scores" ], "h1": "Cartesia Sonic TTS API + MCP vs Deepgram Text-to-Speech (Aura-2, Flux TTS)", "image": "https://www.anchorterminal.com/assets/og/compare-cartesia-tts-vs-deepgram-tts.png", "path": "/compare/cartesia-tts-vs-deepgram-tts", "published": "2026-10-01", "section": "tools", "title": "Cartesia Sonic TTS API + MCP vs Deepgram Text-to-Speech (Aura-2, Flux…", "toc": null, "updated": "2026-10-05", "url": "https://www.anchorterminal.com/compare/cartesia-tts-vs-deepgram-tts" }, "tokens": { "markdown": 1800, "slim": 380 }, "version": 1 }