AssemblyAI vs Soniox pricing
STT: AssemblyAI from $0.0025 vs Soniox from $0.0017.
Last updated · prices checked daily
Speech-to-text: AssemblyAI vs Soniox
Soniox has the lower listed STT price: $0.0017 per minute (Async (file), token-based) vs $0.0025 for AssemblyAI (Universal-Streaming (English)), about 33% less.
| Vendor | Product / tier | $/min |
|---|---|---|
| Soniox Visit site ↗ | Async (file), token-based Token-billed; Soniox's own per-hour equivalent. | $0.0017 |
| Soniox Visit site ↗ | Real-time (streaming), token-based Token-billed; Soniox's own per-hour equivalent. | $0.002 |
| AssemblyAI Visit site ↗ | Universal-Streaming (English) | $0.0025 |
| AssemblyAI Visit site ↗ | Universal-2 (pre-recorded) | $0.0025 |
| AssemblyAI Visit site ↗ | Universal-3.5 Pro (pre-recorded) | $0.0035 |
What it costs at volume (lowest listed rate)
| Minutes | AssemblyAI | Soniox |
|---|---|---|
| 1,000 min | $2.50 | $1.67 |
| 10,000 min | $25.00 | $16.67 |
| 100,000 min | $250.00 | $166.70 |
Cost-per-call calculator
Estimate what one call really costs. Prices come from today's table; LLM and telephony presets are per-minute rates published by Retell and Vapi. Everything is editable.
Cartesia's pricing page puts one minute of speech at 750–800 characters; Rime says about 1,000. The talk share is your own guess at how much of each call the agent is speaking.
FAQ
Is AssemblyAI or Soniox cheaper for speech-to-text?
Soniox has the lower listed STT price: $0.0017 per minute (Async (file), token-based) vs $0.0025 for AssemblyAI (Universal-Streaming (English)), about 33% less. Prices checked Oct 28, 2026.
How often are these prices updated?
Every day. A script reads each vendor's public pricing page, extracts the listed rates and keeps a dated copy, so price changes show up in the history.