A new class of intelligence for real work and powering agents, built to understand complex goals, use tools, check its work, and carry more tasks through to completion. It marks a new way of getting computer work done.
GPT-5.5 gets to what you are trying to do more quickly and can handle more of the work on its own. It is particularly strong at writing and debugging code, researching online, analyzing data, creating documents and spreadsheets, operating software, and working across tools until the task is complete. Instead of managing every step closely, you can hand GPT-5.5 a messy, multi-part task and rely on it to plan, use tools, verify its work, navigate ambiguity, and keep going.
The improvements stand out most in agentic coding, computer use, knowledge work, and early scientific research, areas where progress depends on reasoning across context and taking action over time. GPT-5.5 delivers that increase in capability without giving up speed. Larger and more capable models are often slower, but GPT-5.5 matches GPT-5.4 on per-token latency in real-world serving while operating at a higher level overall. It also uses significantly fewer tokens to complete the same Codex tasks, which makes it more efficient as well as more capable.
The gains are especially clear in agentic coding, computer use, knowledge work, and early scientific research—areas where progress depends on reasoning across context and taking action over time.
The same qualities that make GPT-5.5 strong at coding also make it more effective for everyday computer-based work. It is better at understanding intent, using tools, checking results, and turning rough input into useful output. In Codex, it outperforms GPT-5.4 on documents, spreadsheets, and slide decks, and gets closer to feeling like a model that can actively use the computer alongside you.
Serving GPT‑5.5 at GPT‑5.4 latency required rethinking inference as an integrated system, not a set of isolated optimizations. Codex and GPT‑5.5 were instrumental in how we achieved our performance targets.[…] Put simply, the model helped improve the infrastructure that serves it.
GPT-5.5 is available in the Responses and Chat Completions APIs with a 1M context window.
GPT-5.5-pro is also available in the Responses API for higher-accuracy work.
