OpenAI Ships GPT-Realtime-2.1 and GPT-Realtime-2.1-mini for Low-Latency Voice Agents

OpenAI has released two new models via its Realtime API: GPT-Realtime-2.1 and a smaller GPT-Realtime-2.1-mini, both targeting low-latency voice agent applications. These models are accessible now through the API, meaning developers building voice interfaces, phone bots, or multimodal agents can swap them in immediately. The mini variant is positioned for cost- and latency-sensitive deployments where full model quality is less critical than response speed. This continues OpenAI's push to make real-time speech a first-class API primitive rather than a bolted-on feature. Developers working on voice-first agents should test these against existing Whisper plus TTS pipelines to evaluate end-to-end latency and quality tradeoffs.