{"id":78084,"title":"🔥 Retell AI – API for building human-like conversational voice AI","tagline":"We help developers implement human-like voice agents in a day instead of months. Plug in your LLM, a voice agent in born!","body":"**Tl;dr:** You can now use our [API](https://docs.re-tell.ai/introduction) to build human-like voice AI agents with your LLM. We've achieved response times averaging 800ms, reaching the level of human interactions. (see our [demo](https://youtu.be/0LT64_mgkro) or call +1 (415) 831-7577 to try it out).\n\n### **Problem — Building human-like voice AI agents is hard**\n\n* **Human-like interaction is hard**: Building a voice AI agent that can talk seems easy (stitching together speech-to-text, LLM, and text-to-speech), but making it interact like humans is hard. In human conversation, one has to respond fast and handle all kinds of situations (handling interruptions, knowing when it's your turn to speak, etc).\n* **Long development time**: Developers building voice products spend hundreds of hours focusing on the voice conversation experience alone.\n* **Quality often falls short**: Current voice AI products often have long response latency (**\\\u003e3s**), do not know when to appropriately speak (might interrupt you too much, or respond not quickly enough), and do not handle user interruptions well (AI and human talking over each other), and the list goes on.\n\n  ![uploaded image](/media/?type=post\u0026id=78084\u0026key=user_uploads/1654051/f2832b96-ad0a-4a02-9f1a-8bd461f6dcf8)\n\n\n### **Solution — API for building human-like voice AI agents**\n\n* **Human-Like Conversations**: With our [API](https://docs.re-tell.ai/introduction), you can build a superior voice conversation experience with your LLM. We've achieved response times averaging 800ms, reaching the level of human interactions. We also handle interruptions and provide smart turn-taking determination to achieve seamless conversational exchanges.\n* **Connect your LLM easily**: Plug in your LLM and create a human-like voice agent easily.\n\n  ![uploaded image](/media/?type=post\u0026id=78084\u0026key=user_uploads/1654051/12a8df9f-56f3-4387-a7aa-82727edcc5e4)\n\n* **WebSocket Support:** Connect directly with your users through your web frontend or via phone. You won't have to manage audio bytes – we'll handle that for you.\n\n  ![uploaded image](/media/?type=post\u0026id=78084\u0026key=user_uploads/1654051/5d27fa59-5e8e-4887-b4b1-e8fdee9681a4)\n\n\n\n### **Who is this product meant for?**\n\nAnyone building a voice experience can benefit from using Retell AI. Whether you're developing **AI call agents, AI coaching apps, or AI lifelike companions**, we are your trusted ally in creating the best conversational experience for your users.\n\n### **How to get started?**\n\n* Try our live demo at \u003chttps://www.re-tell.ai/\u003e (no signup needed)\n* Self-serve by registering an account\n* Explore our API Documentation at \u003chttps://docs.re-tell.ai/introduction\u003e\n\n![uploaded image](/media/?type=post\u0026id=78084\u0026key=user_uploads/1654051/a55072bd-520d-4f62-960a-1a064ec53256)\n\n### **Have questions?**\n\n* You can email us at [founders@re-tell.ai](mailto:founders@re-tell.ai)\n* Or schedule a meeting with us at \u003chttps://calendly.com/retell-ai/30min?back=1\u0026month=2024-01\u003e\n* We'll understand your use cases, guide you through our product, and help you quickly implement your voice AI use case.\n\n### **Our Ask:**\n\n* Give us a [try](https://www.re-tell.ai/)! We provide founder's support dedicated to helping you succeed. Please don't hesitate to schedule a meeting with us anytime!\n* If you know anyone who could benefit from Retell AI, we would appreciate a warm introduction. :)\n\n  ![uploaded image](/media/?type=post\u0026id=78084\u0026key=user_uploads/1654051/39f54325-2b20-4e72-84d9-d89be3981d1f)\n\n\nWarm regards from the five-founders' team. (From left to right: [Todd](https://linkedin.com/in/zhengtaoli), [Weijia](https://linkedin.com/in/weijia-y-76b816194), [Zexia](https://linkedin.com/in/zexia-zhang-171480133), [Bing](https://linkedin.com/in/binw) \u0026 [Evie](https://www.linkedin.com/in/yanwang131415/))","slug":"KJQ-retell-ai-api-for-building-human-like-conversational-voice-ai","created_at":"2024-02-02T01:51:47.994Z","updated_at":"2026-07-22T04:04:26.364Z","total_vote_count":129,"url":"https://www.ycombinator.com/launches/KJQ-retell-ai-api-for-building-human-like-conversational-voice-ai","share_image_url":"//bookface-static.ycombinator.com/assets/ycdc/yc-og-image-c440a0ad1dacfb86eeeb343717479cc54d256614449b4ef719977a0a451f8bc8.png","company":{"id":29441,"name":"Retell AI","slug":"retell-ai","url":"https://retellai.com","logo":"https://bookface-images.s3.amazonaws.com/small_logos/c0856f230de1a84be083cff84a3298664d32f0a3.png","batch":"Winter 2024","industry":"B2B","tags":["Artificial Intelligence","AI"],"search_path":"https://bookface.ycombinator.com/company/29441"}}