Transcribe audio
AssemblyAI
Speech-to-text API that transcribes recorded and live audio into text with word timestamps, speaker labels and analysis options.
Billing
- Pricing model
- Pay as you go, per hour of audio submitted; streaming per hour the connection is open5
- Free tier
- $50 in free credits for pre-recorded and real-time speech-to-text, Speech Understanding and Guardrails; credits do not expire5
- Card required for free tier
- No1
- Minimum spend
- None5
- Billing period
- Prepaid balance drawn down with use; end-of-month invoicing for enterprise customers5
- Auto-pay
- Optional recharge when the balance falls below a threshold5
- Free credits and LLM Gateway
- LLM Gateway is not covered by the free credits5
Prices
Dollars per hour of audio, as listed. Streaming is billed per hour the WebSocket is open, not per hour of audio sent. Multichannel files are billed per channel. Add-ons are added to the base rate.
| Model | Mode | $ per hour |
|---|---|---|
universal-3-5-pro (Universal-3.5 Pro) | Pre-recorded | $0.21 |
universal-2 (Universal-2) | Pre-recorded | $0.15 |
universal-3-6-pro (Universal-3.6 Pro Realtime) | Streaming, per session hour | $0.45 |
universal-streaming-english | Streaming, per session hour | $0.15 |
universal-streaming-multilingual | Streaming, per session hour | $0.15 |
Source1Pricing (LLM-readable)
Other charges
| Add-on | $ per hour added |
|---|---|
| Speaker diarization, pre-recorded (standard) | $0.02 |
| Speaker diarization, pre-recorded (experimental) | $0.065 |
| Speaker diarization, streaming | $0.12 |
| Keyterms prompting, Universal-3.5 Pro | $0.05 |
| General prompting (beta), Universal-3.5 Pro | $0.05 |
| Medical Mode | $0.15 |
| Translation | $0.06 |
| Entity detection | $0.08 |
| Sentiment analysis | $0.02 |
| PII text redaction | $0.08 |
| PII audio redaction | $0.05 |
| Content moderation | $0.15 |
Source1Pricing (LLM-readable)
Read from AssemblyAI’s own pages on 2026-11-04. Every number links to the page a value came from. For agents, the same facts as markdown: /tools/transcribe-audio/assemblyai.md