Which platform has lower latency?

In real-world benchmarks, Retell AI typically offers lower end-to-end latency compared to Vapi, while ElevenLabs provides the fastest raw components but can have higher latency when integrated into a third-party stack.

Latency Comparison

Retell AI: Generally considered the leader for integrated voice agents, with end-to-end latency optimized at approximately 450ms to 600ms. It uses a custom-built "turn-taking" model that reduces delays by handling interruptions more naturally than standard API-stitched systems.

Vapi: Offers more flexibility but typically experiences higher latency, ranging from 600ms to 900ms depending on the configuration. Because Vapi allows you to "bring your own" components (like different LLMs or TTS providers), latency can vary significantly based on your specific setup.

ElevenLabs: While their Flash v2.5 model features ultra-low inference speeds of ~75ms, this is just for the voice synthesis part. When used inside a voice agent platform (like Vapi or Retell), the total latency increases because it must account for speech-to-text, LLM processing, and network round-trips.

Which to Choose?

For Lowest Latency Out-of-the-Box: Retell AI is optimized for speed without requiring manual tuning.
For Customization/Developers: Vapi is better if you want to swap models to find the perfect balance of cost and speed for your specific use case.
For Best Voice Quality: ElevenLabs remains the gold standard for emotional range and realism, and they now offer their own ElevenAgents platform to compete directly with Retell and Vapi.

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