Model comparison
Compare GPT-Live 1 and GPT-Realtime-2.1 using the same provider-sourced voice & realtime rubric. No mystery score and no invented benchmark ranking.
Facts checked September 11, 2026
Quick take
OpenAI's full-duplex voice frontend for natural conversation that delegates deeper reasoning and actions to a separate backend agent.
Speech interruption does not automatically cancel backend work. Your application still owns permissions, confirmations, cancellation, durable task state, result validation, and playback safeguards.
OpenAI's realtime speech-to-speech reasoning model for tool-using voice agents that also need text and image context.
There is no published universal latency number, and audio-token costs are hard to compare directly with minute- or character-priced competitors.
Compare the published facts
Values use each provider's own published units and limits. A blank means the provider did not publish a directly comparable value in the sources reviewed.
| Voice & realtime | GPT-Live 1 | GPT-Realtime-2.1 |
|---|---|---|
| Price basisToken-, character-, or minute-based price for the listed access route. | $0.05 / voice minute + backend usage | Audio $32 in · $64 out / 1M tokens |
| Interaction modeSpeech-to-speech, audio-to-audio, or streamed text-to-speech behavior. | Full-duplex voice frontend with delegated backend | Speech-to-speech with text/image context |
| Published latencyProvider-published measurement with its stated exclusions; not a Cody test. | Not published | Not published |
| LanguagesProvider-documented language coverage or a clear unpublished marker. | Multiple accents, dialects, and languages; exact list not published | Multilingual; exact list not published here |
| Tools & controlNative function calling, reasoning, or speech-control features. | Responses or client delegation to backend agents and tools | Function calling and configurable reasoning |
| Context or input limitDocumented token or character limit where it is meaningful. | Not published | 128K input · 32K max output |
How to choose
Start with the job you need to complete, then validate cost, access, and policy details on your exact provider route.
OpenAI says API content is not used for training by default. Default abuse-monitoring logs may be retained up to 30 days, with additional controls available to qualifying organizations.
Provider and API links
OpenAI says API content is not used for training by default. Default abuse-monitoring logs may be retained up to 30 days, with additional controls available to qualifying organizations.
Provider and API links
Frequently asked questions
GPT-Live 1: OpenAI's full-duplex voice frontend for natural conversation that delegates deeper reasoning and actions to a separate backend agent. GPT-Realtime-2.1: OpenAI's realtime speech-to-speech reasoning model for tool-using voice agents that also need text and image context.
Consider GPT-Live 1 when your priority is Natural customer-service and scheduling calls. Consider GPT-Realtime-2.1 when your priority is Tool-using customer or employee voice agents. Test both with your own data and provider route before committing.
No. This comparison aligns provider-published facts for the Voice & realtime category. It does not claim a universal winner or combine incompatible third-party benchmark scores.
