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One API for every frontier LLM

One OpenAI-compatible API for every frontier model — with automatic fallbacks, zero markup, and zero data retention.

Metaview
Dovetail
Granola
Apollo.io
Ashby
Siro
Calabrio
Cluely
Genio
Commure
Retell
CallRail
LiveKit
Earmark
ClickUp
HeyGen
Metaview
Dovetail
Granola
Apollo.io
Ashby
Siro
Calabrio
Cluely
Genio
Commure
Retell
CallRail
LiveKit
Earmark
ClickUp
HeyGen
Metaview
Dovetail
Granola
Apollo.io
Ashby
Siro
Calabrio
Cluely
Genio
Commure
Retell
CallRail
LiveKit
Earmark
ClickUp
HeyGen
Metaview
Dovetail
Granola
Apollo.io
Ashby
Siro
Calabrio
Cluely
Genio
Commure
Retell
CallRail
LiveKit
Earmark
ClickUp
HeyGen
Production Ready

Easiest, most reliable way to call multiple LLMs

Ship faster, spend less on tokens, and stop losing users to provider outages.

0% markup

Pay provider rates, not gateway rates. Competing gateways add 5% or more to every call.

Automatic fallbacks

Configure backup models per request. When a provider errors or stalls, your call still goes through.

Security by simplicity

Pay the exact same price as calling the model provider directly. No markup, no hidden fees, no minimum commitment. We make it simple.

OpenAI-compatible

Drop into any OpenAI SDK. Change a base URL and a model string, and everything keeps working.

Voice-native

Your LLM calls run where your transcription does. One less network hop on every turn.

Models worth using

Frontier models from OpenAI, Anthropic, Google, and open source. New ones added the day they launch.

Built for Voice AI

The LLM layer for Voice AI

One key, one bill for your entire Voice AI pipeline

Function calls and fallbacks fire mid-stream

Typed JSON out of the box, schema-enforced

Cached prompts cost less and respond faster

Live demo

Pick a model. Take action on your audio.

Prompt

What is runner's knee?

claude-opus-4-7 412 ms · 47 tokens

Based on the transcript, runner's knee is a condition characterized by pain behind or around the kneecap. It is caused by overuse, muscle imbalance and inadequate stretching. Symptoms include pain under or around the kneecap and pain when walking.

Built deeper than the alternatives

Model
AssemblyAI LLM Gateway
OpenRouter
llmgateway.io
Bridges to
25+ models, every major provider
400+ models
200+ models
Speech-to-text integration
Native — no extra hop
Routes to third-party ASR
Automatic fallbacks
Configurable per-model
Auto-routing + retries
Pricing
0% markup
~5.5% credit fee
5% managed fee
Same-day model releases
EU data residency
EU-resident, default-on for EU traffic
Enterprise-only
Regional pins only
Zero data retention
Opt-in, per request
Via ZDR-provider routing
OpenAI SDK compatible

AI Speech-to-Text transcription in 99 languages

From Spanish to Korean, deliver accurate Voice AI in the languages your users speak.

Common questions