GPT-5.1 Chat
by OpenAI
GPT-5.1 Chat (AKA Instant is the fast, lightweight member of the 5.1 family, optimized for low-latency chat while retaining strong general intelligence. It uses adaptive reasoning to selectively “think” on harder queries, improving accuracy on math, coding, and multi-step tasks without slowing down typical conversations. The model is warmer and more conversational by default, with better instruction following and more stable short-form reasoning. GPT-5.1 Chat is designed for high-throughput, interactive workloads where responsiveness and consistency matter more than deep deliberation.
Specifications
Technical details and pricing.
Benchmarks
10 benchmark scores from Artificial Analysis.
Composite Indices
Intelligence, Coding, Math
Standard Benchmarks
Academic and industry benchmarks
Frequently Asked Questions
What is GPT-5.1 Chat good for?
Use GPT-5.1 Chat for everyday tasks like writing, summarizing, brainstorming, and getting clear explanations.
How much does GPT-5.1 Chat cost?
Pricing is based on usage. Current rates are $1.25/1M tokens for input and $10.00/1M tokens for output.
Can I try GPT-5.1 Chat for free?
Yes. You can start a chat instantly and test the model before deciding on a plan.
Does GPT-5.1 Chat support images or audio?
GPT-5.1 Chat can understand images.
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Benchmarks and pricing are sourced from Artificial Analysis where available. OpenRouter specs are used as a fallback.