# Best Voice agents — Bring your own key

> Source: https://theagentsindex.com/best/voice-agents/byok (curated, quality-gated, re-verified)

6 of 13 voice agents have a confirmed yes for “Bring your own key”. 3 are qualified or tier-scoped, 2 are confirmed no, and 2 remain not established. Only confirmed yes answers appear in this set; an unknown is never treated as a negative.

| # | Name | What it is | Pricing | API |
| --- | --- | --- | --- | --- |
| 1 | [Cartesia](https://theagentsindex.com/cartesia.md) | Streaming text-to-speech and speech-to-text APIs with a managed runtime for deployed voice agents. | freemium | Yes |
| 2 | [Deepgram Voice Agent API](https://theagentsindex.com/deepgram-voice-agent-api.md) | One WebSocket API that runs speech-to-text, LLM orchestration and text-to-speech for real-time voice agents. | paid | Yes |
| 3 | [ElevenLabs ElevenAgents](https://theagentsindex.com/elevenlabs-conversational-ai.md) | Voice and chat agent platform built on ElevenLabs speech models, deployed to web, mobile and telephony. | freemium | Yes |
| 4 | [LiveKit Agents](https://theagentsindex.com/livekit-agents.md) | Open-source framework and hosted realtime infrastructure for building and running production voice agents | freemium | Yes |
| 5 | [PolyAI](https://theagentsindex.com/polyai.md) | Enterprise platform for building and running voice and chat agents that resolve customer calls | paid | Yes |
| 6 | [Vapi](https://theagentsindex.com/vapi.md) | Developer platform for building, testing and deploying voice AI agents over phone, SIP and the web. | paid | Yes |

## Methodology

Projected from the live listing datasheets using the tenant’s “Your own inference, your own keys, or your own cloud?” axis. Membership requires a sourced yes; partial and unknown answers are reported above but excluded from the ranking. Entries retain the directory’s paid-tier ordering, visibly labelled on every promoted card.