Speech-to-text APIs · Comparison
AssemblyAI vs Deepgram vs Google Cloud Speech-to-Text
3 products compared side by side: what you pay for with each one first, then the five access facts, entry prices, recorded plan limits and the bottom line of each review. The evidence note under the table says how each product was checked.
Side by side
| Metric | AssemblyAI | Deepgram | Google Cloud Speech-to-Text |
|---|---|---|---|
| What you're paying for | Compliance includedA transcription API whose BAA, training opt-out and retention controls are self-serve on paid accounts, with diarized batch audio from $0.17 an hour. | Worth the priceSpeaker-labelled transcripts of pre-recorded audio at $0.0043 a minute with nothing extra to add, plus regional endpoints and a self-hosting path for later. | Built-in reachSpeech recognition inside your Google Cloud account, with IAM, audit logs, a BAA and EU processing, and dynamic batch at $0.003 a minute. |
| Overall score | 8.4Best | 6.6 | 7.8 |
| Free option | Free trial | Free trial | Free plan |
| Card to start | No card needed | No card needed | Card required |
| Getting access | Self-serve | Self-serve | Self-serve |
| Starter priceCheapest paid plan | $0.15/hr | $0.0043/min | $0.003/min |
| Pricing model | Usage-based | Usage-based | Usage-based |
| Pricing page | Public prices | Public prices | Public prices |
| Billing unit | Per second of pre-recorded audio; streaming by session time, idle included; multichannel per channel | Per second of audio; multichannel billed per channel | Per second of audio, no minimum; each channel billed |
| Free credit | $50 at sign-up, no card, does not expire | $200 at sign-up, no card | 60 minutes a month on the V1 API; none on V2 |
| Streaming rate | Universal-Streaming $0.15/h; Universal-3.6 Pro Realtime $0.45/h | Nova-3 Monolingual $0.0077/min regular; $0.0048/min limited-time promotional | $0.016/min ($0.96/h), the same as batch |
| Diarization | Batch +$0.02/h; streaming +$0.12/h (beta in the docs) | Included on pre-recorded audio; streaming +$0.0020/min | No separate price; Chirp 3 diarization in batch only |
| Languages | 99 on Universal-2; 18 on Universal-3.5 Pro | 45+ (pricing page) | Over 125 (product page) |
| Training on your audio | By default; paid accounts opt out online, free accounts cannot | By default; opt out per request (mip_opt_out=true) | Not without your permission; V1 data logging opt-in gives a lower rate |
| HIPAA BAA | Signed online at no cost on paid plans | Enterprise, through sales | Covered; accepted in the console per the docs |
| EU processing | EU endpoint for batch and streaming, same price as US | EU endpoint with existing keys, no plan limit stated; also Australia and India | Chirp 3 GA in the eu multi-region |
| Self-hosted | Streaming only, $20,000 upfront commitment | Enterprise containers; Amazon SageMaker route with an AWS account | Speech-to-Text On-Prem on GKE, through sales |
| SOC 2 / ISO 27001 | SOC 2 Type 2; ISO 27001:2022 | SOC 2 Type II (report on request); ISO 27001 not stated | SOC 2 Type II and ISO 27001 (Compliance Reports Manager) |
| Console SSO | SAML/OIDC add-on, $199/month per connection | Not documented | SAML through Cloud Identity Free, no listed cost |
| Bottom line | From its public pages, AssemblyAI combines the lowest 500-hour price here with compliance controls you switch on yourself: a BAA, a training opt-out and retention as short as an hour. A few add-on prices differ between its pages. | From its public pages, Deepgram pairs low batch rates, diarization included, with a $200 credit and self-hosting. Model improvement is on unless each request opts out, the BAA is Enterprise only, and streaming runs on promotional rates. | From its public pages, Google Cloud Speech-to-Text suits teams inside Google Cloud: no training without permission, a BAA, EU processing and dynamic batch at $0.003 a minute. Features need checking per model, and there is no PII redaction. |
Evidence: AssemblyAI: facts checked 2026-10-16 from its public sign-up and pricing pages, no completed hands-on run; Deepgram: facts checked 2026-10-16 from its public sign-up and pricing pages, no completed hands-on run; Google Cloud Speech-to-Text: facts checked 2026-10-16 from its public sign-up and pricing pages, no completed hands-on run. Prices in USD as listed, excluding tax. "–" means not recorded.
When to pick each
In the words of each review, with the date its facts were checked.
From our AssemblyAI review
Checked Oct 16, 2026- Pick AssemblyAI when
- You want a BAA signed online, a DPA with the terms, ISO 27001 and a delete API.
- Pick Deepgram when
- You want diarization included in the batch rate, a $200 credit and self-hosted containers for batch as well as streaming.
From our AssemblyAI review
Checked Oct 16, 2026- Pick AssemblyAI when
- You want PII redaction, a $50 credit with no card and every add-on priced per hour.
- Pick Google Cloud Speech-to-Text when
- You already use Google Cloud and want its IAM, audit logs and BAA under your existing account.
From our Deepgram review
Checked Oct 16, 2026- Pick Deepgram when
- You want the largest free credit, diarization included in the batch rate, or a self-hosted option beyond streaming.
- Pick AssemblyAI when
- You want a BAA signed online, a DPA with the terms, ISO 27001, a delete API and a lower 500-hour cost ($85 a month on Universal-2, computed).
From our Google Cloud Speech-to-Text review
Checked Oct 16, 2026- Pick Google Cloud Speech-to-Text when
- You want training off by default and Google Cloud IAM, audit logs and SSO at no listed cost.
- Pick AssemblyAI when
- You want PII redaction, a $50 credit with no card and a BAA signed online in a speech-only account.
Entry price
Baseline: each product's cheapest paid plan, per month. Included usage differs, so read the line under each price.
- AssemblyAIUniversal-2, pre-recorded$0.15/hrBilled per second; 99 languages
- Diarization +$0.02/h
- Keyterm prompting included (pricing page)
- PII redaction +$0.08/h
- Word timestamps and confidence included
- DeepgramNova-3 Monolingual, pre-recorded$0.0043/min$0.26/h; Growth $0.0036/min; billed per second
- Speaker diarization and smart formatting included
- Word timestamps and confidence
- Keyterm prompting +$0.0013/min
- Redaction +$0.0020/min
- Google Cloud Speech-to-TextV2 standard recognition$0.016/minFirst 500,000 min a month; then $0.01, $0.008 and $0.004
- Batch, sync and streaming at one price
- Chirp 3 priced at $0.016 on the product page
- Diarization and speech adaptation with no separate price
Prices as listed on each pricing page, in USD per month, excluding tax. Observed: AssemblyAI 2026-10-16, Deepgram 2026-10-16, Google Cloud Speech-to-Text 2026-10-16.
Which one fits
- If you need to start today without a sales call
- AssemblyAISelf-serve sign-up, no card needed; the highest score of the 3 self-serve products here (8.4/10).
- If you want to try it without entering a card
- AssemblyAIFree trial, no card needed, and the highest score of the 2 that skip the card (8.4/10).
- Highest overall score
- AssemblyAI8.4/10 (Excellent). The review shows the score breakdown and the run behind it.
Picked by fixed rules from the table above, not by hand. How we score
Full reviews
Add a product
Search by product name or by what it does, such as “email” or “feature flags”. 1 more fits in this comparison.