Vapi is a developer platform for building, testing and deploying voice AI agents that handle phone and web calls. The platform combines speech-to-text, a language model and text-to-speech, and you connect it to your own systems through an API and SDKs. You can use default providers or substitute your own, including OpenAI, Anthropic, ElevenLabs, Deepgram and Twilio. Flow Studio is a drag-and-drop tool for designing conversation flows, and there are tools for call tracking, testing and analytics. Vapi is delivered as a hosted service.
Vapi is based in San Francisco. According to its Trust Center, authentication data is processed on infrastructure in the United States from 31 July 2026, and its data platform Databricks is hosted in the US. For customers in the EEA, the UK and Switzerland, transfers to the US take place under standard contractual clauses. Vapi does not name a fixed EU hosting region; optional providers, for example for transcription, can be enabled by the customer. A European organisation therefore needs to confirm for itself where voice and conversation data ends up.