OpenAI API — December, 2025

December 1, 2025

This release introduces the new flagship GPT-5.2 model, offering significant advancements in general intelligence, multimodality, code generation, and tool calling. Key new capabilities include xhigh reasoning effort, concise reasoning summaries, and context management via compaction. Additional highlights include new advanced image generation models, improved audio snapshots for real-time voice applications, and the specialized GPT-5.1-Codex-Max for complex coding tasks. Client-side compaction for long conversations and custom voice support further enhance the API experience for developers.

Added

Added gpt-image-1.5 and chatgpt-image-latest to the Responses API image generation tool.
Released gpt-image-1.5 and chatgpt-image-latest, our latest and most advanced models for image generation. Read more here.
Released four new dated audio snapshots. These updates deliver reliability, quality, and voice fidelity improvements for real-time, voice-driven applications. Read more here.
Released GPT-5.2, the newest flagship model in the GPT-5 model family. GPT-5.2 shows improvements over the previous GPT-5.1 in:
What's new in 5.2 is a new xhigh reasoning effort level, concise reasoning summaries, and new context management using compaction.
Released client-side compaction. For long-running conversations with the Responses API, you can use the /responses/compact endpoint to shrink the context you send with each turn.
Released gpt-5.1-codex-max to the Responses API. GPT-5.1-Codex is our most intelligent coding model optimized for long-horizon, agentic coding tasks. Read more here.

Changed

gpt-4o-mini-transcribe-2025-12-15
This launch also includes support for Custom voices for eligible customers.
General intelligence
Instruction following
Accuracy and token efficiency
Multimodality—especially vision
Code generation—especially front-end UI creation
Tool calling and context management in the API
Spreadsheet understanding and creation.