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Head to head · Speech-to-text · October 2026 research run

Google Cloud Speech-to-Text vs OpenAI Speech to Text

OpenAI Speech to Text scores 72.4 (BB) on agent readiness against Google Cloud Speech-to-Text's 70.2 (BB), and leads in 3 of 7 scored categories. Google Cloud Speech-to-Text leads on reliability, security & auth and transparency & trust. Both do speech-to-text.

Best speech-to-text APIs for AI agents · All 91 stt comparisons

Google Cloud Speech-to-TextGoogle Cloud · Model API BB70.2/100#159 of 950 OpenAI Speech to TextOpenAI · Model API BB72.4/100#106 of 950

Which one, for what

Google Cloud Speech-to-Text BB

Good for Google Cloud teams with audio already in Cloud Storage who want no training and no retention by default.

Ahead on

  • Reliability, 85 against 80
  • Security & auth, 95 against 86
  • Transparency & trust, 86 against 61

Watch for

No release note since 2025-11-13

OpenAI Speech to Text BB

Good for Suited to plain transcription of recorded files at a low price a minute and to teams already holding an OpenAI key.

Ahead on

  • Schema & documentation, 88 against 80
  • Agent ergonomics, 78 against 70
  • Maintenance & community, 75 against 25

Watch for

whisper-1, gpt-4o-transcribe, gpt-4o-mini-transcribe and gpt-4o-transcribe-diarize were deprecated on 26 August 2026 and shut down on 26 February 2027

Score by category

CategoryWeight this runGoogle Cloud Speech-to-TextOpenAI Speech to TextEdge
Reliability16%208580Google Cloud Speech-to-Text +5
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28088OpenAI Speech to Text +8
Agent ergonomics13%16.27078OpenAI Speech to Text +8
Security & auth14%17.59586Google Cloud Speech-to-Text +9
Payments & pricing10%12.52020even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.82575OpenAI Speech to Text +50
Transparency & trust7%8.88661Google Cloud Speech-to-Text +25
Negative events≤1500
Total70.2 · BB72.4 · BB

Facts side by side

FactGoogle Cloud Speech-to-TextOpenAI Speech to Text
KindModel APIModel API
VendorGoogle CloudOpenAI
Hosted endpointhttps://speech.googleapis.com/v2https://api.openai.com/v1
TransportsHTTPHTTP, websocket
AuthOAuthAPI key
PricingFreemiumPay per use
x402nono
LicenceApache-2.0 (SDKs)Proprietary hosted service. The service terms were not read (see open questions). The Python SDK is Apache-2.0 and the OpenAPI document is MIT
Read-only variant documentednono
llms.txtnoyes
Last release2026-09-282026-08-26
Terms last updated2026-09-02couldn't be read
Privacy policy last updated2026-10-01couldn't be read
Customer content may train modelsyescouldn't be read
Terms restrict automated accessnot found in the textcouldn't be read
Terms restrict benchmarkingnot found in the textcouldn't be read
Terms or service can change without noticenot found in the textcouldn't be read
Arbitration or class-action waivernot found in the textcouldn't be read
Popularity713k npm/wk, 3.7M PyPI/wk32k stars
Agent reviews3/5 (2)none

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.

OpenAI Speech to Text

gpt-transcribe costs $0.0045 an audio minute, and the audio endpoints keep no abuse-monitoring logs or application state. Speaker labels, timestamps, subtitles and translation exist only on whisper-1 and gpt-4o-transcribe-diarize, which shut down on 26 February 2027 with no named replacement for those functions.

Before you call either

Google Cloud Speech-to-Text

  1. Call Chirp 3 on the us or eu endpoint. It isn't listed for the global location
  2. Reopen streams before the 5-minute limit, or use BatchRecognize for recordings
  3. Downmix stereo unless you need channel labels, since each channel is billed
  4. Set dynamic batch on offline jobs to cut the price from $0.016 to $0.003 a minute
  5. Back off on RESOURCE_EXHAUSTED. The Speech docs don't give a retry interval

OpenAI Speech to Text

  1. Send gpt-transcribe to POST /v1/audio/transcriptions for recorded files. Use languages (a list), not language, and never send both.
  2. Keep each upload at 25 MB or less. Split longer audio between sentences and pass the previous chunk's text in prompt.
  3. For speaker labels send gpt-4o-transcribe-diarize with response_format=diarized_json and chunking_strategy=auto for audio over 30 seconds. Plan for its shutdown on 26 February 2027.
  4. Word timestamps, srt, vtt and /v1/audio/translations need whisper-1, which cannot stream and shuts down on the same date.
  5. On 429 or 503 wait at least Retry-After when present, then back off with jitter. Do not retry credit_balance_exhausted or spend-limit errors.

Questions

Which is better for AI agents, Google Cloud Speech-to-Text or OpenAI Speech to Text?

OpenAI Speech to Text scores 72.4 (BB) on agent readiness against Google Cloud Speech-to-Text's 70.2 (BB), and leads in 3 of 7 scored categories. Google Cloud Speech-to-Text leads on reliability, security & auth and transparency & trust.

Do Google Cloud Speech-to-Text and OpenAI Speech to Text need an API key?

Google Cloud Speech-to-Text uses an OAuth sign-in. OpenAI Speech to Text needs an API key.

Can an agent call Google Cloud Speech-to-Text and OpenAI Speech to Text without installing anything?

Yes. Google Cloud Speech-to-Text has a hosted endpoint at https://speech.googleapis.com/v2 and OpenAI Speech to Text at https://api.openai.com/v1.

Other comparisons with Google Cloud Speech-to-Text or OpenAI Speech to Text

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