Retell AI

What Is Retell AI?

Retell AI is a speech API platform that lets large language models (LLMs) interact through natural, human-like voices in your applications. It combines speech-to-text, LLMs, and text-to-speech components so developers can build Voice AI that feels like a real conversation.

Standout features include realistic voices, smooth handling of interruptions, quick response times, extensive customization options, and straightforward integration with existing LLMs and frontends. The company is backed by Combinator and focuses on creating fluid, lifelike conversational Voice AI.

Who’s Behind Retell AI?

Retell AI was founded by Peer Richelsen, Tyler Bosmeny, and Rajat Suri, former executives from well-known tech companies. Their goal is to make LLMs better at human-like voice conversations through a platform offering realistic voices, smart interruption handling, low latency, and easy integration.

What Can You Do with Retell AI?

• Add voice to LLMs: Let your models interact with users through natural-sounding voices.
• Build conversational Voice AI: Create agents that hold human-like conversations.
• Integrate key technologies: Combine speech-to-text, LLMs, and text-to-speech in one pipeline.
• Customize behavior: Adjust features like noise reduction and analyze sentiment in the voice.
• Handle interruptions: Keep conversations natural when users cut in.
• Connect your systems: Integrate with your current LLMs and frontend applications.
• Respond quickly: Benefit from low-latency responses that keep conversations flowing.

Who Should Use Retell AI?

• Developers
• Teams building Voice AI applications

Getting Started

1. Create an agent: Sign up on the Retell AI website and use the dashboard to create an agent with a simple prompt — no coding required. You can also link it to a phone number.
2. Review demos and docs: Test the platform through the dashboard, then explore the documentation and tutorials for production use.
3. Connect telephony: Link Retell AI with Twilio to make phone calls; an open-source demo repository helps with setup. Other providers like Vonage also work.
4. Security and compliance: Retell AI follows HIPAA regulations and is working toward SOC2 Type II certification.

Summary

Retell AI gives developers the tools to build voice agents that sound natural and respond quickly, with a Turn-Taking model, strong interruption handling, and integrations for common telephony providers.