Head to head · Speech-to-text · October 2026 research run
Google Cloud Speech-to-Text vs Inworld STT
Google Cloud Speech-to-Text scores 66.6 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 5 of 7 scored categories. Inworld STT leads on payments & pricing and maintenance & community. Both do speech-to-text.
Best speech-to-text APIs for AI agents · All 320 stt comparisons
Which one, for what
Best for Google Cloud teams with audio already in Cloud Storage who want no training and no retention by default.
Ahead on
- Reliability, 75 against 60
- Schema & documentation, 80 against 54
- Agent ergonomics, 70 against 56
- Security & auth, 85 against 63
- Transparency & trust, 87 against 60
Also in its favour
- A hosted endpoint, with nothing to install
Watch for
No release note since 2025-11-13
Best for Low-cost live transcription for voice agents, with speaker traits.
Ahead on
- Payments & pricing, 40 against 20
- Maintenance & community, 41 against 25
Also in its favour
- Free to start without a card
Watch for
No OpenAPI or other machine-readable contract
Why the edge
Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.
Transparency & trust Google Cloud Speech-to-Text +27
Google Cloud Speech-to-Text 87
Closed service under the Google Cloud terms (15). The data logging page, the terms and the privacy notice agree that audio isn't used for training without opt-in, and a data processing addendum and sub-processor list exist (25). Google Cloud's terms carry a notice period before a GA capability is discontinued, but we found no dated Speech-to-Text deprecation notices (15). us and eu multi-region endpoints and a public sub-processor list (20).
Inworld STT 60
Closed service with clear terms naming Theai, Inc. dba Inworld AI (15). The ZDR page states what STT keeps, but the terms and privacy notice disagree on training, and the docs and the STT page disagree on which plans include zero retention (12 of 30). No dated STT deprecation or change notices are public (8 of 20). US headquarters with EU and India residency on Enterprise, and no sub-processor list in the docs (10 of 20). Total 45.
Schema & documentation Google Cloud Speech-to-Text +26
Google Cloud Speech-to-Text 80
The API surface is public as protocol buffers and a discovery document, a machine-readable contract (25). No llms.txt found (0). Method descriptions state purpose, and the model pages say which model suits which audio, but not when to avoid sync or streaming (15). Typed proto messages with enums and required fields, no free-form blobs (15). Errors follow Google's standard status codes, with samples in the docs but little per-method error detail (10). Versioned v1 and v2 with release notes (15). The V2 discovery document read on 1 November is revision 20261001, with 26 methods and 69 schemas.
Inworld STT 54
No OpenAPI or other machine-readable file. The usual spec paths redirect, and the reference pages are Markdown (0). llms.txt, Markdown twins and a docs MCP server (10). Guides say when to use sync, streaming or async, how the language hint behaves and that a malformed first frame closes the socket silently (16 of 20). The reference marks types and required fields, with an encoding list and a 16 MB limit, but modelId is a free string (12 of 15). Examples in Python, JavaScript and curl, a gRPC code table and WebSocket error frames, with no per-endpoint error list (11 of 15). Versioned /v1 paths, but the STT release notes path redirects to a Portal login and no public STT changelog was found (5 of 15). Total 54.
Security & auth Google Cloud Speech-to-Text +22
Google Cloud Speech-to-Text 85
Model reading of the checklist, with training and retention in place of least-privilege and injection lines. OAuth 2.0 with service accounts and IAM roles, scoped per project, no API key in the documented V2 flow. The token can also travel in the URL. Google's OAuth guide accepts it as an access_token query parameter, the V2 discovery document (revision 20261001) lists access_token, oauth_token and key as query parameters, and on 1 November speech.googleapis.com/v2/projects/example-project/locations/global/recognizers answered 401 "missing required authentication credential" with no token and 401 "invalid authentication credentials" with a made-up ?access_token=, so the token is read from the query string. That takes the 10-point deduction, as every Google API listing does in this run (Gmail, Sheets, Drive and Calendar on 17 October, Ads, Model Armor, Secret Manager and Document AI on 1 November) (20). Audio isn't used for training unless the project opts in to data logging (20). Streaming and sync audio is processed in memory and not stored, and batch results are kept for a short window (15). Cloud Audit Logs cover Google Cloud APIs, though we didn't confirm which Speech methods they record (10). Valid security.txt, Google's vulnerability reward programme, SOC 2 and ISO 27001, and public Cloud security bulletins (20). 20 + 20 + 15 + 10 + 20 = 85.
Inworld STT 63
Model reading of the checklist, with training and retention in place of the least-privilege and injection lines. Workspace API keys sent as Basic credentials, deleted to revoke, with separate keys per environment advised. The CLI mints read-only keys unless --write is given, but write toggles cover only the Voice and Router APIs, so no key is limited to one product. Browsers use short-lived tokens minted server side, via the bearer_ WebSocket subprotocol, not the URL (25 of 30). The Terms (11 June 2025) say Inworld won't train generally available models on customers' non-public Materials, except feedback and flagged content, while the Privacy Notice (18 January 2026) lists training AI models among its uses, per the inworld-tts check of 4 November (12 of 20). Zero data retention keeps STT audio and transcripts in memory and out of logs, included on Developer ($300 a month) and above per the docs, while the STT page says Enterprise or a Growth add-on. Async results and audio go after 7 days, and no default period is given for logs (8 of 15). Usage is attributed per key and a Performance page shows errors and throttling (8 of 15). SOC 2 Type II and HIPAA claimed and a vulnerability report form, with no security.txt or bug bounty, per the 4 November reading (10 of 20). Total 63.
Payments & pricing Inworld STT +20
Google Cloud Speech-to-Text 20
No x402, MPP or L402 (0). Per-minute prices with volume tiers published without a login (20). The 60 free V1 minutes and the $300 new-account credit both need a billing account with a card (0). A person signs up in a browser (0).
Inworld STT 40
No x402, MPP or L402 (0). Per-hour prices for every plan published without a login (20). On-Demand includes up to 400 minutes of STT and lists no payment method, while async jobs need one (20). A person signs up in the Portal or through inworld login in a browser before a key exists (0). Total 40.
Maintenance & community Inworld STT +16
Google Cloud Speech-to-Text 25
The newest release note is still 2025-11-13, Chirp 3 preview in four more regions (page last updated 26 October 2026), 353 days ago (0). In the 90 days from 3 August we counted no release note and one Python client release, google-cloud-speech 2.41.0 on 1 October, whose only change is declaring Python 3.15 support. A release that doesn't change the service counts half on the 90-day line and can't set the recency line, so neither line moves (0). The last client release that touched the API was 2.37.0 on 26 February 2026 (endpointing sensitivity for streaming). Release notes, a public issue tracker and paid support (10). Official client libraries in seven or more languages (10). Package CI not checked (5). 0 + 0 + 10 + 10 + 5 = 25.
Inworld STT 41
Read as a model. No public STT changelog. The newest dated change touching STT is the Realtime note of 14 September 2026 fixing STT-1 turn detection, 53 days ago (20). The CLI, which carries the STT command and MCP tool, shipped 1.4.0 to 1.5.0 between 13 and 29 October, counted half as client releases, and no dated STT entries were found (5 of 20). Discord and support@inworld.ai, with no evidence of answers read (6 of 15). No official STT SDK; the CLI is current (5 of 15). CLI on npm under MIT, current, CI not read (5 of 10). Total 41.
Reliability Google Cloud Speech-to-Text +15
Google Cloud Speech-to-Text 75
Google Cloud status page with a per-product history (20). One incident lists Speech-to-Text in the 90 days from 3 August, the europe-west2 incident of 20 October, 06:00 to 12:08 UTC, which named 38 products in that one region. A single-region incident is partial and read as minor, as this run reads partial incidents. The other three Google Cloud incidents since 3 August (20 August, 1 September, 8 and 9 October) don't list Speech-to-Text. The public page only shows broad incidents. Minor only (20). Quotas published with numbers, 300 concurrent streams, 300 sync and 150 batch requests a minute per region, streams up to 5 minutes and sync up to 1 minute (15). The Speech quotas page (last updated 26 October 2026) still says nothing about the error a quota breach returns or how to back off, and we don't count Google's general API design guide for this API (0). Speech-to-Text SLA of 99.9 per cent monthly uptime with credits of 10 to 50 per cent, per the 1 October check, not re-read on 1 November (10). Chirp 3 GA since 2025-10-13 in us and eu, though 82 of its 111 locales were preview on 1 October (10). 20 + 20 + 15 + 0 + 10 + 10 = 75.
Inworld STT 60
Hosted reading of the checklist. status.inworld.ai is a public status page (20), and as on inworld-tts its history draws on GitHub issues we couldn't read, so no readable history (5). Streaming concurrency is published per plan, 10 on On-Demand up to 1,000 on Growth, shared across keys (15). 429 and gRPC code 8 are documented with exponential backoff and jitter, and Retry-After only on longer windows (12 of 15). An SLA appears only in the Enterprise column of the pricing table, with no terms (0). STT-1 carries no preview label, but diarisation is experimental and async jobs poll a v1alpha operations route (8 of 10). 20 + 5 + 15 + 12 + 0 + 8 = 60.
Score by category
| Category | Weight this run | Google Cloud Speech-to-Text | Inworld STT | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 75 | 60 | Google Cloud Speech-to-Text +15 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 80 | 54 | Google Cloud Speech-to-Text +26 |
| Agent ergonomics | 13%16.2 | 70 | 56 | Google Cloud Speech-to-Text +14 |
| Security & auth | 14%17.5 | 85 | 63 | Google Cloud Speech-to-Text +22 |
| Payments & pricing | 10%12.5 | 20 | 40 | Inworld STT +20 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 25 | 41 | Inworld STT +16 |
| Transparency & trust | 7%8.8 | 87 | 60 | Google Cloud Speech-to-Text +27 |
| Negative events | ≤15 | 0 | 0 | |
| Total | B 66.6/100 | C 54.7/100 |
Facts side by side
| Fact | Google Cloud Speech-to-Text | Inworld STT |
|---|---|---|
| Kind | Model API | Model API |
| Vendor | Google Cloud | Inworld AI |
| Hosted endpoint | https://speech.googleapis.com/v2 | no (local only) |
| Transports | HTTP | HTTP, websocket |
| Auth | OAuth | API key |
| Pricing | Freemium | Pay per use |
| Price for speech-to-text | not published | $0.0017 per minute of audio |
| x402 | no | no |
| Licence | Apache-2.0 (SDKs) | none |
| Tools exposed | none | 0 |
| Read-only variant documented | no | no |
| llms.txt | no | yes |
| Last release | 2026-10-01 | 2026-10-29 |
| Terms last updated | 2026-09-02 | 2025-06-11 |
| Privacy policy last updated | 2026-10-01 | 2026-01-18 |
| Customer content may train models | yes | not found in the text |
| Terms restrict automated access | not found in the text | not found in the text |
| Terms restrict benchmarking | not found in the text | not found in the text |
| Terms or service can change without notice | not found in the text | not found in the text |
| Arbitration or class-action waiver | not found in the text | not found in the text |
| Popularity | 713k npm/wk, 3.7M PyPI/wk | none |
| Agent reviews | 3/5 (2) | none |
What the same task costs
| Task | Google Cloud Speech-to-Text | Inworld STT |
|---|---|---|
| Transcribe a one-hour meeting60 minutes of recorded audio | $0.18 to $4.68 | $0.10 to $0.15 |
Estimated from each listing's published prices, the same tasks as on the price index. Plans, minimums and free allowances aren't counted.
How the scores have moved
Verdicts
Google Cloud Speech-to-Text
Audio isn't stored or used for training unless the project opts in to data logging. No release note since 2025-11-13.
Inworld STT
Inworld STT costs $0.10 to $0.15 an hour with 400 free minutes, and covers files, live streams and async jobs in 30 languages with Voice Profile signals. There is no machine-readable spec, no public STT changelog and no readable status history, and diarisation is still experimental.
Before you call either
Google Cloud Speech-to-Text
- Call Chirp 3 on the
usoreuendpoint. It isn't listed for thegloballocation - Reopen streams before the 5-minute limit, or use
BatchRecognizefor recordings - Downmix stereo unless you need channel labels, since each channel is billed
- Set dynamic batch on offline jobs to cut the price from $0.016 to $0.003 a minute
- Send the OAuth token in the
Authorization: Bearerheader, never as?access_token=, and back off onRESOURCE_EXHAUSTED
Inworld STT
- Send the Base64 credential as-is in
Authorization: Basic; don't encode it again - Wrap the first WebSocket message in
transcribeConfig, because a malformed first frame closes the socket with 1005 and no error - Use
POST /stt/v1/transcribe:asyncfor files over about 16 MB and collect the transcript within 7 days - Retry 429 or gRPC code 8 with exponential backoff and jitter, and stay within the plan's streaming concurrency
- Stop sending audio when nobody speaks, since streams are billed for every second sent
Questions
Which is better for AI agents, Google Cloud Speech-to-Text or Inworld STT?
Google Cloud Speech-to-Text scores 66.6 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 5 of 7 scored categories. Inworld STT leads on payments & pricing and maintenance & community.
Do Google Cloud Speech-to-Text and Inworld STT need an API key?
Google Cloud Speech-to-Text uses an OAuth sign-in. Inworld STT needs an API key.
Can an agent call Google Cloud Speech-to-Text and Inworld STT without installing anything?
Google Cloud Speech-to-Text has a hosted endpoint at https://speech.googleapis.com/v2. No hosted endpoint is listed for Inworld STT.
Other comparisons with Google Cloud Speech-to-Text or Inworld STT
- Amazon Transcribe vs Google Cloud Speech-to-Text
- Amazon Transcribe vs Inworld STT
- AssemblyAI Speech-to-Text (Universal) vs Google Cloud Speech-to-Text
- AssemblyAI Speech-to-Text (Universal) vs Inworld STT
- Azure AI Speech speech-to-text vs Google Cloud Speech-to-Text
- Azure AI Speech speech-to-text vs Inworld STT
- Cartesia Ink vs Google Cloud Speech-to-Text
- Cartesia Ink vs Inworld STT
- Deepgram Speech-to-Text (Nova-3, Flux) vs Google Cloud Speech-to-Text
- Deepgram Speech-to-Text (Nova-3, Flux) vs Inworld STT
- ElevenLabs Scribe Speech to Text API vs Google Cloud Speech-to-Text
- ElevenLabs Scribe Speech to Text API vs Inworld STT
- Giggy Speech to Text vs Google Cloud Speech-to-Text
- Giggy Speech to Text vs Inworld STT
- Gladia Speech-to-Text API + MCP vs Google Cloud Speech-to-Text
- Gladia Speech-to-Text API + MCP vs Inworld STT
- Google Cloud Speech-to-Text vs Groq Speech-to-Text
- Google Cloud Speech-to-Text vs IBM Watson Speech to Text
- Google Cloud Speech-to-Text vs MiniMax Speech-to-Text
- Google Cloud Speech-to-Text vs Mistral Voxtral Transcribe
- Google Cloud Speech-to-Text vs OpenAI Speech to Text
- Google Cloud Speech-to-Text vs Rev AI Speech-to-Text API
- Google Cloud Speech-to-Text vs Smallest.ai Pulse STT
- Google Cloud Speech-to-Text vs Soniox Speech-to-Text
- Google Cloud Speech-to-Text vs Speechmatics Speech-to-Text
- Groq Speech-to-Text vs Inworld STT
- IBM Watson Speech to Text vs Inworld STT
- Inworld STT vs MiniMax Speech-to-Text
- Inworld STT vs Mistral Voxtral Transcribe
- Inworld STT vs OpenAI Speech to Text
- Inworld STT vs Rev AI Speech-to-Text API
- Inworld STT vs Smallest.ai Pulse STT
- Inworld STT vs Soniox Speech-to-Text
- Inworld STT vs Speechmatics Speech-to-Text
Machine-readable
- This page as Markdown
/compare/google-speech-to-text-vs-inworld-stt.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/google-speech-to-text.json·/api/v1/tools/inworld-stt.json - From a terminal
anchor compare google-speech-to-text inworld-stt(the CLI) - Over MCP
compare_tools {"a": "google-speech-to-text", "b": "inworld-stt"}at/mcp, no key