OpenAI has launched GPT-Live-1 in the API, bringing the natural voice model first introduced in ChatGPT to developers building voice applications and business workflows. The model listens and speaks at the same time, handles interruptions and acknowledgments as they happen, and can keep a conversation moving while deeper reasoning or actions run through paired models and tools such as GPT-6 Astra, Codex, and ChatGPT Work.

Unlike traditional voice agents that chain speech recognition, a reasoning model, and speech synthesis, GPT-Live-1 processes incoming and outgoing audio together. OpenAI says this avoids latency and fragile handoffs that can lose timing, context, and conversational rhythm. Developers can control tone, pace, and style through the system prompt, select their own backend model and agent harness, and use ASR transcripts, response text, keyword biasing, alphanumeric recognition, and native turn detection. Telephony support targets reservations, order updates, and customer service, while the model is designed to handle background noise and silence without talking over users or narrating every step.

GPT-Live-1 brings ChatGPT’s natural, full-duplex conversations to the API, with more control over how voice agents speak and act. This lets users build apps and workflows powered by bidirectional voice.

Early results point to a sharp change in turn-taking. Speak reported almost 80% fewer interruptions than with previous turn-based systems, giving language learners more time to think. OpenAI says GPT-Live-1 gained 30 percentage points over GPT-Realtime-2.1 on Full Duplex Bench and ranked first on Tau3 when paired with GPT-6 Astra at medium reasoning effort. Early users include Yelp Host, Speak, Intercom's Fin, and Cognition's Devin. One customer said the move from a cascaded system cut its voice codebase by 80% and removed 23,000 lines used for real-time patient conversations.

The release gives OpenAI a front-end voice layer that can sit above a separately chosen and priced reasoning stack. GPT-Live-1 costs $0.05 per minute in the API, with backend model and agent harness fees charged separately. It launches with 12 voices spanning accents, dialects, and languages, while custom voice access requires contacting sales. OpenAI plans to add more voices and languages and points enterprises to Presence for real-time workflows that can use company systems, take approved actions, and escalate to people.