Use case · Developer infrastructure
Best voice infrastructure for developers
These are the building blocks you wire together yourself: APIs, SDKs and frameworks for speech, turn-taking and call control, rather than a finished agent. Pick these when you are building a voice product, not buying one off the shelf.
What to look for: Look for clear docs and SDKs, bring-your-own model and voice, low latency you can measure, and usage-based pricing that scales with your own product.
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The speed specialist whose fast, natural speech is what keeps a live phone agent feeling real rather than laggy.
Build a phone agent exactly the way you want it, choosing each part yourself, if you have a developer to hand.
The open-source real-time stack that carries voice-agent audio, plus a framework to wire your own STT, LLM and voice.
A voice that picks up how the caller is feeling and answers in kind, for warmer and more human conversations.
Open-source Python framework where you pick every voice-agent part, free to self-host, with Daily's cloud for scaling.
Enterprise text-to-speech built for high-stakes phone calls, where a mispronounced name loses the customer.
Get the voice agent and the phone network it runs on from one provider, useful when you want billing in one place.
OpenAI's speech-to-speech model and API for building your own voice agent, billed by audio tokens, not by the minute.
The best canvas for designing chat and voice agents, but a builder you wire up, not a turnkey phone product.
Fast, accurate speech-to-text to power high-volume voice apps, for teams happy to build on a developer API.
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Accurate streaming speech-to-text with built-in audio intelligence, for teams who want the listening half done well.
Enterprise speech-to-text with very broad language coverage and real on-prem options, for teams who self-host.
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