# Open-source voice frameworks: compare vendors

There are 4 open-source voice frameworks vendors in the index.

4 voice AI vendors. Also on the [web page](https://voiceagents.fyi/us/global/online/category/open-source-voice-frameworks).

## Voice AI vendors

1. [LiveKit](https://voiceagents.fyi/us/global/online/livekit.md), Open-source voice frameworks, Online: An open source framework and developer platform for building, testing, deploying, scaling, and observing agents in production.
2. [SignalWire](https://voiceagents.fyi/us/global/online/signalwire.md), Voice AI APIs, Online: Build AI voice agents, contact centers, and unified communications on one programmable platform. One control plane, no vendor stitching.
3. [Ultravox](https://voiceagents.fyi/us/global/online/ultravox.md), Voice AI APIs, Online: Ultravox is a real-time voice AI infrastructure layer that powers fast, natural, and scalable voice agents.
4. [Rasa](https://voiceagents.fyi/us/global/online/rasa.md), Open-source voice frameworks, Online: Agent platform for product teams building customer-facing AI, including voice assistants; originates from the open-source Rasa framework.

## Other categories in Online

- [Contact-centre voice AI](https://voiceagents.fyi/us/global/online/category/contact-center-voice-ai.md): 41 voice AI vendors
- [AI receptionists](https://voiceagents.fyi/us/global/online/category/ai-receptionists.md): 32 voice AI vendors
- [Voice AI APIs](https://voiceagents.fyi/us/global/online/category/voice-ai-apis.md): 30 voice AI vendors
- [Voice agent platforms](https://voiceagents.fyi/us/global/online/category/voice-agent-platforms.md): 28 voice AI vendors
- [Healthcare voice AI](https://voiceagents.fyi/us/global/online/category/healthcare-voice-ai.md): 22 voice AI vendors
- [Outbound and sales calling](https://voiceagents.fyi/us/global/online/category/outbound-sales-calling.md): 18 voice AI vendors
- [Hospitality voice AI](https://voiceagents.fyi/us/global/online/category/hospitality-voice-ai.md): 9 voice AI vendors