PyAI vs Vapi
Run the whole voice agent - STT, reasoning, retrieval, and TTS - on one speech-to-speech model and one socket, with telephony-grade turn-taking instead of cross-vendor hops. Vapi advertises a ~$0.05/min platform fee, but that's only the orchestration layer: add STT, an LLM, TTS, and telephony and the all-in lands ~$0.10-$0.31/min, each billed separately. PyAI is $0.05/min all-in - one key, one bill, no asterisk. Vapi still shines when provider choice is the point.
Why teams pick PyAI over Vapi
One model runs the whole call - not a stitched pipeline.
One speech-to-speech model, not seven boxes
Omni is a single model: audio in, audio out. No stitching STT, VAD, turn detection, an LLM, RAG, and TTS together - so there's one thing to ship and nothing between the hops to break.
Built for telephony (8 kHz)
Tuned for narrowband phone audio, not studio takes - so accuracy and turn-taking hold up on real lines, backed by a billion conversations across our portfolio.
Human conversational pace, with barge-in
~390 ms median voice-to-voice (in-region) with barge-in and warm transfer - conversations feel like a person, not a walkie-talkie. Early in-region measurement, not an SLA.
Grounded, tool-using, and OpenAI-compatible
Answers from your knowledge base, calls your tools, and drops into an OpenAI-realtime-compatible URL - so switching is about two lines of code.
What you get by switching
- One PyAI key instead of multiple provider keys
- No platform-fee-plus-passthrough surprise
- ~390 ms voice-to-voice, in-region
- OpenAI-compatible realtime alias
- Trace and the Agents feature available when you scale
Choose PyAI when
Developers who want to stop stitching providers and paying four bills, and still keep an API-native workflow.
Where Vapi fits
Vapi remains useful when picking your own STT/LLM/TTS providers is the primary requirement.
PyAI vs Vapi, in one chart
All-in price per minute (USD)
Lower is better. PyAI in teal. The bar spans each platform’s typical all-in range.
All-in, billed per second, speech + brain + telephony in one rate. $0.05/min Omni API, $0.08/min for the no-code Agents feature.
Advertised from ~$0.09/min self-serve → all-in $0.11-$0.14/min once LLM, voice, and telephony are added.
Advertised agent minutes + LLM → all-in $0.10-$0.15/min once LLM, voice, and telephony are added.
Advertised no-code plans → all-in $0.11-$0.16/min once LLM, voice, and telephony are added.
Advertised ~$0.05/min platform fee → all-in $0.10-$0.31/min once LLM, voice, and telephony are added.
Advertised ~$0.07/min platform → all-in $0.13-$0.31/min once LLM, voice, and telephony are added.
PyAI is one flat all-in rate, billed per second. Packaged figures are the advertised platform fee plus STT/LLM/TTS/telephony passthrough estimates as of June 2026, composite and config-dependent, so verify before relying on them.
Where voice AI spend leaks
Hidden costs to watch for
- Platform fees or seats that must be paid before usage creates value
- Pass-through STT, realtime model, TTS, telephony, and orchestration bills that are hard to forecast
- Credit or character pricing that hides the cost of long calls and long-form audio
- Manual QA, compliance review, and call summaries that only happen after the expensive mistake
How PyAI helps you prove the switch
PyAI keeps testing free and migration practical: free credits, OpenAI-compatible surfaces where supported, transparent all-in minute pricing, and production add-ons for QA, compliance, summaries, and grounding.
And then there's the price
Once the capability fits, the economics seal it - one transparent all-in rate, billed per second.
PyAI
All-in for Omni API.
One socket, one bill, per-second billing, and one all-in rate for the full voice loop - no platform fee plus four passthrough bills.
Vapi
All-in ~$0.10-$0.31/min once STT, LLM, TTS, and telephony are added (estimated as of writing - verify).
Public pricing and market estimates as of June 2026; verify before relying on procurement numbers.
Model your own numbers
Plug in your call volume and see the all-in cost side by side - no sales call required.
Replacement plan: Vapi to PyAI
- 1
Model your current all-in cost per minute, including every provider and platform fee.
- 2
Move one call path to PyAI with the migration guide or OpenAI-compatible base URL swap.
- 3
Replay real calls and compare latency, completion rate, transcript quality, and spend.
- 4
Route production traffic gradually, then add Trace, Recap, or the Agents feature where the workflow needs review.
FAQ
When should I choose PyAI over Vapi?
Developers who want to stop stitching providers and paying four bills, and still keep an API-native workflow.
How does PyAI pricing compare with Vapi?
PyAI pricing: $0.05/min all-in for Omni API.. Vapi pricing: ~$0.05/min platform fee advertised; all-in ~$0.10-$0.31/min once STT, LLM, TTS, and telephony are added (estimated as of writing - verify).. Public comparison data should be verified before procurement decisions.
Where do businesses usually waste money in voice AI?
Waste usually comes from platform fees, per-seat packaging, pass-through model bills, credit or character math, and manual QA work that does not scale to every call.
How do I test a replacement without a risky rewrite?
Start with one call path, use a PyAI test key and free credits, replay real calls, and compare quality, latency, completion rate, and all-in cost before routing production traffic.
One voice stack. One bill. Built for phone agents.
Start with $50 in free credit. No card.
Agents is live in beta. Sandbox keys have daily limits and never touch billing.