Vapi
Free trialLiveLast verified 27 Sept 2026
Hosted voice agents for phone and web calls that combine your choice of speech, LLM and voice providers.
Example request
curl -s 'https://api.vapi.ai/assistant' -H "Authorization: Bearer $API_KEY"
Free tier, in plain English
New accounts get $5 of free credit and a free US number to try voice agents. After that you prepay per minute, starting at $0.05 a minute for Vapi hosting plus model, voice and phone costs.
Alternatives in Voice
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All 3 Voice APIs →