Speech-to-text APIs · Comparison

AssemblyAI vs Deepgram vs Speechmatics

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

AssemblyAI vs Deepgram vs Speechmatics: value, access facts, plan limits and bottom lines
Metric	AssemblyAI	Deepgram	Speechmatics
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.	Compliance includedTranscription in 55+ languages where your audio stays out of model training unless you opt in, with EU, US and Australian processing for every account.
Overall score	8.4Best	6.6	8.1
Free option	Free trial	Free trial	Free trial
Card to start	No card needed	No card needed	No card needed
Getting access	Self-serve	Self-serve	Self-serve
Starter priceCheapest paid plan	$0.15/hr	$0.0043/min	$0.24/hr
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, from credits at hourly rates; credit price falls with packs and subscriptions
Free credit	$50 at sign-up, no card, does not expire	$200 at sign-up, no card	$100 at sign-up, no card, valid 12 months
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	Melia 1 $0.40/h; Standard $0.45/h; Enhanced $0.80/h (list)
Diarization	Batch +$0.02/h; streaming +$0.12/h (beta in the docs)	Included on pre-recorded audio; streaming +$0.0020/min	Included; real-time speaker labels on Enhanced, Standard and Linden, not Melia 1
Languages	99 on Universal-2; 18 on Universal-3.5 Pro	45+ (pricing page)	55+ (pricing page); 56 for Melia 1
Training on your audio	By default; paid accounts opt out online, free accounts cannot	By default; opt out per request (mip_opt_out=true)	Only if you opt in (33% off)
HIPAA BAA	Signed online at no cost on paid plans	Enterprise, through sales	Sub-BAA through the Trust Center; plan and process not stated
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	EU, US and Australia regions for all customers
Self-hosted	Streaming only, $20,000 upfront commitment	Enterprise containers; Amazon SageMaker route with an AWS account	On-prem containers, virtual appliance and on-device on Enterprise
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 (Trust Center, under NDA); ISO/IEC 27001:2022
Console SSO	SAML/OIDC add-on, $199/month per connection	Not documented	SAML/OIDC on Enterprise, $280/month add-on
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, Speechmatics has the strictest privacy defaults of the five: no training unless you opt in, 7-day batch retention and real-time audio not stored. Its pricing page leads with discounted rates, and redaction, SSO and on-prem are Enterprise features.

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; Speechmatics: 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 the lower 500-hour price ($85 against $120 a month, computed) and a BAA you can sign online.
Pick Speechmatics when
You want audio kept out of training by default and streaming diarization at no extra cost on Enhanced and Standard.
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 Deepgram review
Checked Oct 16, 2026
Pick Deepgram when
You want EU, Australia and India endpoints with one key and a $200 credit the pricing page says has no expiration.
Pick Speechmatics when
You want customer audio left out of training by default, batch files deleted after 7 days and streaming diarization included on Enhanced and Standard.
From our Speechmatics review
Checked Oct 16, 2026
Pick Speechmatics when
You want audio kept out of training by default and streaming speaker labels at no extra cost.
Pick AssemblyAI when
You want a BAA signed online, PII redaction as a per-hour add-on and a lower 500-hour price ($85 a month, computed).
From our Speechmatics review
Checked Oct 16, 2026
Pick Speechmatics when
You want training off by default, processor terms in the Terms of Service and a stated 7-day retention.
Pick Deepgram when
You want a larger credit that the pricing page says has no expiration, and self-hosting through Amazon SageMaker.

Entry price

Baseline: each product's cheapest paid plan, per month. Included usage differs, so read the line under each price.

AssemblyAI
Universal-2, pre-recorded
$0.15/hr
Billed per second; 99 languages
- Diarization +$0.02/h
- Keyterm prompting included (pricing page)
- PII redaction +$0.08/h
- Word timestamps and confidence included
Deepgram
Nova-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
Speechmatics
Pro: Melia 1, pre-recorded
$0.24/hr
Pay-as-you-go list rate; $0.16 with the model-training opt-in
- Speaker diarization included
- 56 languages, code-switching
- Word timestamps included

Prices as listed on each pricing page, in USD per month, excluding tax. Observed: AssemblyAI 2026-10-16, Deepgram 2026-10-16, Speechmatics 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 3 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

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