AssemblyAI vs Deepgram (2026): the cheaper transcript or the faster live voice?
AssemblyAI is the speech AI API for recorded and real-time transcription plus audio intelligence — sentiment, entities, PII redaction and summaries — with pay-as-you-go pricing from $0.15 per audio hour and $50 in free credit. Deepgram is the speech API built for speed: Nova-3 and Flux models for streaming and recorded transcription, Aura text-to-speech and a Voice Agent API, with pay-as-you-go pricing from about $0.26 per audio hour and $200 in free credit.
| AssemblyAI | Deepgram | |
|---|---|---|
| Free tier | $50 in free credit for new accounts; no card required to start | $200 in free credit for new accounts, which does not expire; no card required |
| Paid tier | Universal-2 pre-recorded $0.15 per audio hour; Universal-3.5 Pro $0.21; streaming $0.15 per session hour; Universal-3.6 Pro Realtime $0.45 | Nova-3 pre-recorded $0.0043 a minute (about $0.26 an hour); Nova-3 streaming $0.0048 a minute on a promotional rate, $0.0077 regular (about $0.46 an hour) |
| Best for | Developers who need transcripts plus analysis — summaries, sentiment, entities — in one API call | Developers building real-time voice agents, live captions and call analytics where latency matters |
| Standout strength | The cheapest recorded transcription in the category at $0.15 an hour, with a deep add-on library (medical mode, keyterms, PII redaction) and a new text-to-speech API | Streaming-first architecture with sub-second latency, free speaker diarization on recorded audio, and a single Voice Agent API that combines transcription, LLM and speech |
| Watch out for | Streaming is billed on how long the WebSocket stays open, including idle time, and add-ons stack on top of the base rate | Streaming rates are promotional and labelled limited-time — the regular rate is about 60% higher — and diarization costs extra on streaming |
AssemblyAI wins when the transcript is the starting point, not the finish: a recording that also needs a summary, sentiment scores, entity extraction or PII redaction. At $0.15 an audio hour for Universal-2 it undercuts Deepgram's Nova-3 batch rate of about $0.26 an hour, and on 1,000 hours a month that gap is $150 against $258. Its streaming is also cheaper at $0.15 a session hour, though it bills open-connection time including silence, so an unclosed session can cost more than expected.
Deepgram wins when the audio is live: a voice agent, live captions, or call analytics that must respond in under a second. Its Nova-3 and Flux models are built for streaming, and its Voice Agent API bundles transcription, language model and speech into one WebSocket at $0.075 a minute. The catch is the promotional streaming rate — $0.0048 a minute now, $0.0077 regular — so budget on the regular price. If you transcribe files, start with AssemblyAI. If you build live voice products, start with Deepgram.
Sources: official pricing pages and 2026 comparison coverage. AssemblyAI listing · Deepgram listing