Vapi

Vapi is a platform for building voice agents that hold telephone conversations. It handles the orchestration between speech recognition, a language model and a voice, along with the telephony, monitoring and deployment machinery underneath, so a developer can configure conversation flow and integrations rather than assembling that stack themselves. Agents can be built through an API or through a web interface. Typical deployments are customer support lines, lead qualification and appointment scheduling. The platform targets responses in under 500 milliseconds and covers turn taking, custom pronunciation and keyword handling, live access to external data and tools including MCP, and a managed catalog of more than 200 models alongside the option to bring your own. Telephony features include custom SIP support, warm transfers, voicemail detection, number management and DTMF handling. For larger deployments there are conversation guardrails, scenario simulation for testing agents before they reach customers, call level analytics, single sign on, OAuth and role based access control, and SOC 2, HIPAA and PCI compliance. Usage is billed by the minute. Starting is free with $5 in credits, after which Vapi hosting is $0.05 per minute and model, transcription and voice costs pass through at provider rates with no markup. Optional support packages sit on top: Core is $29 per month, Pro is 10 percent of the Vapi hosting fee with a $999 monthly minimum, and Premier is quoted. Extras are priced separately, with HIPAA eligible data handling at $2,000 per month, additional concurrency at $10 per line per month and additional organizations at $20 each per month. Transport is charged by the carrier, with Vapi telephony, WebSockets and Daily WebRTC free, Twilio at $0.008 inbound and $0.014 outbound per minute, Vonage at $0.00814 and Telnyx at $0.0055.