ElevenLabs and Vapi.ai are prominent conversational AI platforms that facilitate the creation of customizable voice agents, each with distinct features and strengths. ElevenLabs distinguishes itself by developing its own in-house text-to-speech (TTS) and speech-to-text (STT) models, which enhances control and reduces latency, making it ideal for applications requiring high-quality voice outputs. In contrast, Vapi.ai offers a flexible, API-native framework that integrates with multiple TTS providers, including ElevenLabs, allowing for diverse voice options and scalability, albeit with potentially higher latency. Both platforms support extensive language capabilities and provide robust tools for API calls, knowledge base management, and telephony integrations, making them suitable for various business applications. The choice between the two largely depends on specific needs such as in-house model integration, customization capabilities, and latency preferences, with ElevenLabs offering low-latency performance and extensive voice libraries, while Vapi.ai emphasizes flexibility and extensive language support.