Tool profile
AssemblyAI: cost, fit and limits
AssemblyAI is a speech AI company that sells speech to text through an API, for both pre-recorded files and live streaming audio, with usage-based rate cards. Its pricing page also lists per-character rates for other products.
What to know first
AssemblyAI gives $50 in free credits on signup without a card, then moves to usage-based pay as you go billed per hour for pre-recorded audio and per session duration for streaming. The free tier allows 5 new streams per minute and pay as you go allows 100. Volume pricing and commit buyouts go through sales. Hourly rates were not captured in our reading.
AssemblyAI at a glance
| Maker | AssemblyAI, Inc., United States |
|---|---|
| Free plan | Yes |
| Entry price | $0.15 per hour |
| API access | Yes |
| Category | Best AI Speech to Text APIs in 2026, rank 7 of 12 |
| Website | assemblyai.com |
Who AssemblyAI is best for
Developers prototyping a live feature
The $50 credit needs no card, and streaming concurrency is printed per tier, so a prototype's limits are known before the first call.
Startups scaling streaming traffic
The jump from 5 new streams per minute on free to 100 on pay as you go gives a clear step for a product growing past its launch phase.
Buyers with committed volume
Enterprise offers volume pricing and commit buyouts through sales, which suits a team that can forecast annual hours and wants a negotiated rate.
AssemblyAI plans and pricing
| Plan | Price | What it includes |
|---|---|---|
| Free tier | $50 in free credits on signup | No credit card required, with a limit of 5 new streams per minute for streaming transcription. |
| Pay as you go | Usage-based rate cards | Allows 100 new streams per minute, with hourly and per-character rates in the rate cards. |
| Enterprise | Custom quote | Volume pricing and commit buyouts arranged through the sales team. Terms such as thresholds and discounts are discussed with the sales team directly. |
Checked October 2026.
What AssemblyAI does
- Pre-recorded billing per hour
- File transcription is billed by the hour of audio, which maps cleanly onto podcasts, meetings and call archives. An hour of audio is the unit, which makes the monthly forecast simple for batch workloads such as archives.
- Streaming billed per session
- Live transcription is billed by session duration rather than by audio minutes, so an open connection that carries silence still counts. Teams should close idle connections promptly, since time spent waiting for speech is billed like time spent in speech.
- Tiered stream limits
- New stream starts are capped per minute, 5 on the free tier and 100 on pay as you go, which limits how fast a launch can ramp.
- Other metered products
- Per-character rates appear on the page for non-transcription products, so the invoice may carry more than one unit if you use them. This matters mainly to buyers who plan to use several products together instead of transcription alone.
How AssemblyAI handles your data
The AssemblyAI pricing page does not state retention periods, whether customer audio is used for model training, hosting regions or certifications, so this entry claims none of them. Enterprise buyers negotiate volume terms through sales, and that conversation is the natural place to ask for data processing terms. The vendor's privacy policy and security documentation were not opened for this entry, and should be read before sending audio that contains personal or regulated data.
Where AssemblyAI falls short in practice
- Credit only on free. The free tier is a one-time signup credit, and the page names no monthly free hours, so ongoing small projects start paying quickly. After the credit is spent, even a weekend side project begins paying the usual rates.
- Stream start limits. The free tier allows only 5 new streams per minute, which is enough to demo but too low for a launch with many simultaneous users.
- Rates not on the page we read. Hourly figures for the rate cards were not captured, so cost per hour has to be confirmed on the live pricing page. Confirm each rate on the live page before building a budget, because this entry cannot quote them.
- Quote-only volume terms. Commit buyouts and volume discounts are negotiated with sales, with no published thresholds, which slows down budgeting for larger teams. No numeric thresholds are published, so a team cannot see what volume would qualify for a discount.
Works with
Alternatives to AssemblyAI
AssemblyAI: common questions
How much free credit does AssemblyAI give?
The pricing page says new accounts receive $50 in free credits on signup with no credit card required. It is a one-time credit, not a monthly allowance, and the free tier also limits streaming to 5 new streams per minute. After the credit runs out, usage moves to pay as you go.
How many streams can AssemblyAI handle?
The pricing page states 5 new streams per minute on the free tier and 100 new streams per minute on pay as you go. It describes new stream starts per minute, so confirm with the vendor how that interacts with total simultaneous connections for your use case.
How does AssemblyAI bill streaming transcription?
Streaming is billed by session duration, while pre-recorded audio is billed per hour. That means the length of an open session matters, so a connection that stays open through silence is charged. Test your session handling to avoid paying for idle time.
Does AssemblyAI publish its hourly rates?
The pricing page presents rate cards with hourly and per-character figures, but the exact amounts were not captured when this entry was written. Read the live page for current rates, and convert them into dollars per audio hour before comparing with other vendors.
Does AssemblyAI use my audio to train models?
The pricing page does not say, so this site cannot confirm it. Ask in writing for the training, retention and hosting terms, and read the vendor's privacy policy, which was not opened for this entry, before sending sensitive recordings. Keep the answer with your vendor file.