{
  "data": {
    "a": {
      "slug": "amazon-polly",
      "name": "Amazon Polly",
      "vendor": "Amazon Web Services",
      "vendorUrl": "https://aws.amazon.com/polly/",
      "kind": "model",
      "category": "text-to-speech",
      "summary": "AWS's speech synthesis API with four engines (standard, neural, long-form and generative) and about 110 voices in 42 languages and variants.",
      "url": "https://www.anchorterminal.com/tools/amazon-polly",
      "markdownUrl": "https://www.anchorterminal.com/tools/amazon-polly.md",
      "slimMarkdownUrl": "https://www.anchorterminal.com/tools/amazon-polly.min.md",
      "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/amazon-polly.json",
      "transports": [
        "http"
      ],
      "remoteUrl": "https://polly.us-east-1.amazonaws.com/v1",
      "packages": [
        {
          "registry": "npm",
          "name": "@aws-sdk/client-polly"
        },
        {
          "registry": "pypi",
          "name": "boto3"
        }
      ],
      "auth": "api-key",
      "authNotes": "AWS Signature Version 4 with IAM access keys or a role. Regional endpoints `polly.\u003cregion\u003e.amazonaws.com`.",
      "pricing": "usage",
      "pricingNotes": "$4 per 1M characters for standard voices, $16 neural, $30 generative and $100 long-form. SSML tags aren't billed. Accounts opened before 2025-07-15 get 5M standard characters a month (and 1M neural for 12 months), newer accounts get Free Tier credits instead (https://aws.amazon.com/polly/pricing/).",
      "priceSummary": "Pay per use",
      "where": "hosted",
      "x402": {
        "level": "no",
        "evidence": "No machine payment. Billing runs through a cloud account with a card or invoice.",
        "endpoints": []
      },
      "toolCount": null,
      "popularity": {
        "githubStars": null,
        "npmWeekly": 743201,
        "pypiWeekly": null,
        "asOf": "2026-09-30"
      },
      "docsUrl": "https://docs.aws.amazon.com/polly/latest/dg/what-is.html",
      "llmsTxt": "https://docs.aws.amazon.com/polly/latest/dg/llms.txt",
      "capabilities": [
        "speech.tts",
        "speech.streaming",
        "speech.voices",
        "speech.ssml",
        "speech.languages"
      ],
      "tags": [
        "hosted",
        "closed-source",
        "python",
        "typescript",
        "enterprise",
        "streaming",
        "batch",
        "async-jobs",
        "llms-txt",
        "card-required"
      ],
      "lastRelease": "2026-08-12",
      "graded": true,
      "anchor": {
        "graded": true,
        "score": 75.8,
        "grade": "BB",
        "agentReady": true,
        "rank": 29,
        "ranked": true,
        "rankOf": 452,
        "categoryRank": 1,
        "methodology": "0.3",
        "run": "2026-10-01",
        "scores": {
          "ergonomics": 82,
          "maintenance": 50,
          "payments": 20,
          "reliability": 100,
          "schema": 90,
          "security": 80,
          "transparency": 80
        },
        "pending": [
          "performance",
          "tasks"
        ],
        "assessment": {
          "confidence": "high",
          "date": "2026-10-01"
        },
        "negative": 0,
        "verdict": "IAM policies scope access per action and resource, and CloudTrail logs each call. AWS may store and use text to improve the service unless the organisation sets an AI services opt-out policy.",
        "strengths": [
          "IAM policies scope access per action and resource, and CloudTrail logs each call",
          "Quotas published per operation and engine, with backoff and jitter guidance for throttling",
          "Covered by the Amazon Machine Learning Language SLA",
          "Standard voices at $4 and neural at $16 per 1M characters",
          "Typed exceptions per action and a public service model in every AWS SDK"
        ],
        "weaknesses": [
          "AWS may store and use text to improve the service unless the organisation sets an AI services opt-out policy",
          "A new account needs a card, and the monthly free characters only apply to accounts opened before 2025-07-15",
          "Neural, long-form and generative synthesis is limited to 8 requests a second by default",
          "Generative voices support only part of SSML",
          "No dated service change since 2026-08-12"
        ],
        "agentNotes": [
          "Keep `SynthesizeSpeech` under 3,000 billed characters, or use `StartSpeechSynthesisTask` for longer text.",
          "Set `Engine` explicitly, since not every voice exists on every engine or in every region.",
          "Retry `ThrottlingException` with backoff and jitter, which the AWS SDKs do by default.",
          "Check the generative SSML tag list before porting neural SSML.",
          "Ask for `OutputFormat` `json` with speech marks when you need word timings."
        ],
        "metrics": {
          "kind": "remote",
          "measured": false
        },
        "reviewCount": 8,
        "avgRating": 4,
        "history": [
          {
            "basis": "public evidence",
            "confidence": "high",
            "grade": "BB",
            "methodology": "0.3",
            "pending": [
              "performance",
              "tasks"
            ],
            "run": "2026-10-01",
            "runLabel": "October 2026 research run",
            "score": 75.8
          }
        ],
        "editorialScores": {
          "ergonomics": 82,
          "maintenance": 50,
          "payments": 20,
          "reliability": 100,
          "schema": 90,
          "security": 80,
          "transparency": 65
        },
        "provenanceScore": 95
      },
      "connect": {
        "install": "pip install boto3   # or: npm i @aws-sdk/client-polly",
        "http": "curl -X POST \"https://polly.us-east-1.amazonaws.com/v1/speech\" \\\n  --aws-sigv4 \"aws:amz:us-east-1:polly\" --user \"$AWS_ACCESS_KEY_ID:$AWS_SECRET_ACCESS_KEY\" \\\n  -H \"content-type: application/json\" -o speech.mp3 \\\n  -d '{\"Engine\":\"neural\",\"VoiceId\":\"Joanna\",\"OutputFormat\":\"mp3\",\"Text\":\"Your table is booked for seven.\"}'"
      },
      "letme": {
        "capability": "https://letme.dev/speech.tts",
        "tool": "https://letme.dev/amazon-polly"
      },
      "sameCompany": [
        "amazon-bedrock-guardrails",
        "amazon-transcribe",
        "aws-secrets-manager",
        "aws-mcp-servers",
        "amazon-ses",
        "amazon-translate"
      ],
      "area": "voice",
      "unitPrices": [
        {
          "item": "Standard voices",
          "unit": "1m-chars",
          "usd": 4
        },
        {
          "item": "Neural voices",
          "unit": "1m-chars",
          "usd": 16
        },
        {
          "item": "Generative voices",
          "unit": "1m-chars",
          "usd": 30
        },
        {
          "item": "Long-form voices",
          "unit": "1m-chars",
          "usd": 100
        }
      ],
      "provenance": {
        "legalEntity": "Amazon Web Services, Inc.",
        "domain": "amazon.com",
        "domainRegistered": "1994-11-01",
        "domainNote": "The endpoints are on amazonaws.com (registered 2005-08-18) and api.aws, both AWS domains. The security.txt on aws.amazon.com passed its Expires date on 2026-09-24.",
        "endpointOnVendorDomain": true,
        "terms": "https://aws.amazon.com/service-terms/",
        "privacy": "https://aws.amazon.com/privacy/",
        "statusPage": "https://health.aws.amazon.com/health/status",
        "changelog": "https://docs.aws.amazon.com/polly/latest/dg/doc-history.html",
        "securityTxt": "expired",
        "checked": "2026-09-30",
        "score": 95
      },
      "pageJsonUrl": "https://www.anchorterminal.com/tools/amazon-polly.json",
      "live": {
        "slug": "amazon-polly",
        "probe": {
          "target": "https://polly.us-east-1.amazonaws.com/v1",
          "method": "get",
          "lastAt": "2026-10-04T23:48:03.882144289Z",
          "lastOk": true,
          "lastStatus": 404,
          "lastMs": 250,
          "authRequired": false,
          "uptime24h": 100,
          "uptime30d": 100,
          "p50ms24h": 253,
          "p95ms24h": 299,
          "samples24h": 272,
          "samples30d": 1100,
          "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": 270,
              "ok": 270
            }
          ]
        },
        "vendorStatus": {
          "page": "https://health.aws.amazon.com/health/status",
          "indicator": "unknown",
          "summary": "no machine-readable status found",
          "checkedAt": "2026-10-04T13:55:53.179828833Z"
        },
        "versions": [
          {
            "registry": "npm",
            "name": "@aws-sdk/client-polly",
            "version": "3.1146.0",
            "seenAt": "2026-10-04T16:20:04.158471769Z"
          },
          {
            "registry": "pypi",
            "name": "boto3",
            "version": "1.43.108",
            "released": "2026-10-02",
            "seenAt": "2026-10-04T16:20:05.799588968Z"
          }
        ],
        "npmWeekly": 810846,
        "pypiWeekly": 577776836,
        "securityTxt": {
          "url": "https://amazon.com/.well-known/security.txt",
          "state": "valid",
          "checkedAt": "2026-10-04T15:15:49.458098289Z"
        },
        "llmsTxt": {
          "url": "https://docs.aws.amazon.com/polly/latest/dg/llms.txt",
          "ok": true,
          "status": 200,
          "checkedAt": "2026-10-04T15:17:14.894515439Z"
        },
        "domain": {
          "domain": "amazon.com",
          "registered": "1994-11-01",
          "source": "https://rdap.verisign.com/com/v1/domain/amazon.com",
          "checkedAt": "2026-10-04T13:06:18.739682554Z"
        },
        "pages": [
          {
            "url": "https://docs.aws.amazon.com/polly/latest/dg/doc-history.html",
            "kind": "changelog",
            "status": 304,
            "checkedAt": "2026-10-04T15:43:16.374349241Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "70fe277f702a"
          },
          {
            "url": "https://aws.amazon.com/polly/pricing/",
            "kind": "pricing",
            "status": 304,
            "checkedAt": "2026-10-04T15:41:28.654188145Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "3d9521893777"
          },
          {
            "url": "https://aws.amazon.com/privacy/",
            "kind": "privacy",
            "status": 304,
            "checkedAt": "2026-10-01T13:11:21.687931657Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "6ebd6be5615f"
          },
          {
            "url": "https://aws.amazon.com/service-terms/",
            "kind": "terms",
            "status": 200,
            "checkedAt": "2026-10-01T13:11:23.703347826Z",
            "changedAt": "0001-01-01T00:00:00Z",
            "fingerprint": "c2276020bd07"
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        ],
        "updatedAt": "2026-10-04T23:48:03.882144289Z"
      }
    },
    "b": {
      "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",
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        "vendorStatus": {
          "page": "https://status.cartesia.ai",
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          "summary": "All Systems Operational",
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        "securityTxt": {
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  "markdown": "Amazon Polly has a score of 75.8 (BB) against Cartesia Sonic TTS API + MCP's 64.2 (B). Both do speech tts. The largest gap is reliability, 37 points.\n\n- Amazon Polly: grade BB, 75.8/100, rank #29 of 452. Markdown https://www.anchorterminal.com/tools/amazon-polly.md · JSON https://www.anchorterminal.com/api/v1/tools/amazon-polly.json\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\n## Which one, for what\n\nPick Amazon Polly for reliability (+37), agent ergonomics (+17), security \u0026 auth (+22), transparency \u0026 trust (+9).\n\nPick Cartesia Sonic TTS API + MCP for payments \u0026 pricing (+10), maintenance \u0026 community (+29).\n\n## Score by category\n\n| Category | Weight | Amazon Polly | Cartesia Sonic TTS API + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 100 | 63 | Amazon Polly +37 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 90 | 86 | Amazon Polly +4 |\n| Agent ergonomics | 13% (16.2 this run) | 82 | 65 | Amazon Polly +17 |\n| Security \u0026 auth | 14% (17.5 this run) | 80 | 58 | Amazon Polly +22 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 20 | 30 | Cartesia Sonic TTS API + MCP +10 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 50 | 79 | Cartesia Sonic TTS API + MCP +29 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 80 | 71 | Amazon Polly +9 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **75.8 · BB** | **64.2 · B** | |\n\n## Facts side by side\n\n| Fact | Amazon Polly | Cartesia Sonic TTS API + MCP |\n| --- | --- | --- |\n| Kind | Model API | Model API |\n| Vendor | Amazon Web Services | Cartesia |\n| Hosted endpoint | `https://polly.us-east-1.amazonaws.com/v1` | `https://api.cartesia.ai` |\n| Transports | HTTP | HTTP, Streamable HTTP, stdio |\n| Auth | API key | OAuth or key |\n| Pricing | Pay per use | Freemium |\n| x402 | no | no |\n| Licence | none | Apache-2.0 (SDKs) |\n| Tools exposed | none | 15 |\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 | 2026-08-12 | 2026-09-30 |\n| Popularity | 743k npm/wk | 133 stars, 166k npm/wk, 177k PyPI/wk |\n| Agent reviews | 4/5 (8) | 3/5 (2) |\n\n## Verdicts\n\n**Amazon Polly.** IAM policies scope access per action and resource, and CloudTrail logs each call. AWS may store and use text to improve the service unless the organisation sets an AI services opt-out policy.\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## Before you call either\n\n### Amazon Polly\n\n1. Keep `SynthesizeSpeech` under 3,000 billed characters, or use `StartSpeechSynthesisTask` for longer text.\n2. Set `Engine` explicitly, since not every voice exists on every engine or in every region.\n3. Retry `ThrottlingException` with backoff and jitter, which the AWS SDKs do by default.\n4. Check the generative SSML tag list before porting neural SSML.\n5. Ask for `OutputFormat` `json` with speech marks when you need word timings.\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## Other comparisons with Amazon Polly or Cartesia Sonic TTS API + MCP\n\n- [Amazon Polly vs Azure AI Speech text-to-speech](https://www.anchorterminal.com/compare/amazon-polly-vs-azure-text-to-speech.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- [Amazon Polly vs ElevenLabs Text to Speech API + MCP](https://www.anchorterminal.com/compare/amazon-polly-vs-elevenlabs-tts.md)\n- [Amazon Polly vs Murf TTS API + MCP](https://www.anchorterminal.com/compare/amazon-polly-vs-murf-tts.md)\n- [Amazon Polly vs PlayHT Text-to-Speech API](https://www.anchorterminal.com/compare/amazon-polly-vs-playht-tts.md)\n- [Amazon Polly vs Resemble AI Text-to-Speech API](https://www.anchorterminal.com/compare/amazon-polly-vs-resemble-ai-tts.md)\n- [Amazon Polly vs Rime TTS API + MCP](https://www.anchorterminal.com/compare/amazon-polly-vs-rime-tts.md)\n- [Amazon Polly vs Soniox Text-to-Speech](https://www.anchorterminal.com/compare/amazon-polly-vs-soniox-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- [Cartesia Sonic TTS API + MCP vs Deepgram Text-to-Speech (Aura-2, Flux TTS)](https://www.anchorterminal.com/compare/cartesia-tts-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",
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    "description": "Amazon Polly has a score of 75.8 (BB) against Cartesia Sonic TTS API + MCP's 64.2 (B). Both do speech tts. The largest gap is reliability, 37 points. Category scores, facts, verdicts and agent notes side by side.",
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