ElevenLabs
State-of-the-art voice synthesis, cloning and conversational audio.
by Vapi · founded 2023 · updated Jul 2026
Vapi is an API-first platform for building, testing and deploying voice AI agents that handle real phone calls. It orchestrates speech-to-text, LLMs and text-to-speech with sub-second latency, and adds telephony, tool calling, squads of agents and call analytics, making it the default infrastructure choice for teams shipping voice agents.
Fixed weights, sources attached, the formula
Each score is built from the claims below. This is a snapshot, so check the current terms with the vendor before you commit to anything.
| Claim | Source | Checked |
|---|---|---|
| Orchestrates STT, LLM and TTS for real-time phone agents with tool calling | Vapi documentation | Jun 2026 |
ElevenLabs
State-of-the-art voice synthesis, cloning and conversational audio.
Otter.ai
The dedicated AI meeting notetaker: live transcription, summaries and follow-up on every call.
Descript
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