← Back to the directoryListed price$0.0035 / minPay-as-you-go information Languages99+Approximate coverage StreamingYesReal-time transcription DiarizationYesSpeaker separation
AssemblyAI.
Speech AI models plus audio-intelligence features on top of transcription.
Directory noteSTT-first vendor; broad audio-intelligence layer.
AssemblyAI speech-to-text API overview
The four signals that usually narrow a speech-to-text shortlist first. Prices are the cheapest documented async tier; native billing units differ, so read the notes below.
AssemblyAI pricing, languages, and features
Everything else the directory currently tracks, kept in one clear spec sheet for comparison.
- Company
- AssemblyAI
- Listed price
- $0.0035 / minBilled per hour. Universal-3.5 Pro async $0.21/hr (~$0.0035/min); Universal-2 async $0.15/hr (~$0.0025/min). Streaming is billed on WebSocket session duration, not audio length.
- Languages
- 9999 applies to Universal-2; the Universal-3.5 Pro flagship supports 18 languages with code-switching.
- Real-time streaming
- Yes
- Speaker diarization
- Yes
- Free tier or trial
- Yes$50 signup credit (marketed as up to 185h prerecorded / 333h streaming). Credit-based, not a perpetual free tier.
- Models
- Universal-3.5 Pro, Universal-2, Universal-Streaming
Pricing, languages, streaming, and diarization verified against AssemblyAI’s primary sources on 2026-08-27. Word error rate and latency are not yet measured.
Official AssemblyAI website and API documentation
Confirm current pricing and capabilities in the provider’s own materials before making a purchasing decision.
Primary sources used to verify this profile
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