AssemblyAI vs Deepgram
A detailed comparison to help you choose between AssemblyAI and Deepgram.
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Verdict: AssemblyAI wins
AssemblyAI scores 4.3/5, edging out Deepgram at 4.2/5. Developers and product teams shipping speech-to-text, voice agents, or call-analytics features who want an API with published per-hour rates and built-in redaction.
AssemblyAI Speech AI models for developers | Deepgram Speech-to-text API with real-time transcription and low latency | |
|---|---|---|
| Rating | 4.3 (1 review) | 4.2 (1 review) |
| Pricing Model | free | usage-based |
| Starting Price | Free | Pricing varies |
| Best For | Developers and product teams shipping speech-to-text, voice agents, or call-analytics features who want an API with published per-hour rates and built-in redaction. | Developers and platform teams building voice features — transcription pipelines, live captioning, voice agents — who want public per-minute pricing, real streaming performance and the option to self-host. |
| Free Tier | ||
| API Access | ||
| Team Features | ||
| Open Source | ||
| Tags | api accessfree tier | api accessfree tier |
| Visit AssemblyAI → | Visit Deepgram → |
AssemblyAI
Pros
- + Transparent, published rate card: $0.15/hr for Universal-2 and $0.21/hr for Universal-3.5 Pro at time of writing (assemblyai.com/pricing.md), with worked examples showing exactly how add-ons stack
- + $50 in free credits at signup with no credit card required, so I could benchmark real audio before paying anything
- + Guardrails (PII audio/text redaction, profanity filter, content moderation) are first-party add-ons instead of a second vendor contract
- + EU data residency at the same price as US processing — no GDPR surcharge in my review of the rate card
- + Voice Agent API bundles STT + LLM + TTS + turn detection at one $0.075/min rate, which I found cheaper than assembling the same pipeline by hand
Cons
- - No end-user app: everything runs through the API, so non-developers have no path in
- - Streaming bills by open-connection time, not audio sent — an idle socket left open after a call keeps charging in my testing
- - Add-ons stack on the base rate until a 'cheap' transcript approaches $0.40–$0.60/hr for the feature set most teams want
- - Long-file processing is async only; no synchronous option for large uploads
- - Legacy Auto Chapters and Summarization add-ons are deprecated and can fail silently on newer models per the vendor's own pricing reference
Deepgram
Pros
- + Per-second billing with no rounding up — my 47-minute test metered exactly 2,820 seconds against APIs that would have billed 48 or 60 minutes
- + Every self-serve rate is on a public pricing page, including BYO-LLM and BYO-TTS Voice Agent tiers from $0.05/min
- + One-time $200 signup credit with no card and no expiry covers roughly 700 hours of pre-recorded Nova-3 transcription
- + Self-hosted deployment is real and documented, via an official Helm chart covering STT, TTS and the Voice Agent API on Kubernetes
- + Streaming latency held up in testing and matches independent benchmarks (Coval measured Nova-3 at 85 ms mean time to final segment, October 2026)
Cons
- - Streaming prices are promotional with no end date and the regular rates printed alongside are 59-60% higher — budget for $0.0077/min, not $0.0048/min
- - Support is community and Discord only below Enterprise, even on the $4,000+/year Growth plan
- - No recurring free tier: the $200 credit is one-time, and Deepgram measures its coverage against the cheapest configuration
- - No end-user product at all — no editor, dashboard or export tools for non-technical teams
- - Accuracy on accented, noisy or mono audio trails the strongest models; Coval ranks Nova-3 19th of 30 on mixed-sample word error rate
Frequently Asked Questions
Which is better, AssemblyAI or Deepgram?▼
AssemblyAI scores higher at 4.3/5 vs 4.2/5 for Deepgram, making it the better-rated option in our comparison.
What is the difference between AssemblyAI and Deepgram?▼
AssemblyAI: AssemblyAI is a developer API that converts recorded or live speech into text, with speaker labels and options to summarise transcripts. Pay-as-you-go from about $0.15 per audio hour. Deepgram: Deepgram provides speech-to-text, text-to-speech and voice agent APIs for developers, with real-time transcription built for high volumes.
Is AssemblyAI or Deepgram more affordable?▼
AssemblyAI pricing varies, Deepgram starts at €0/mo. Check the comparison table above for current pricing.
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