GPT-5.1 Chat
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...
What is GPT-5.1 Chat?
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...
Specifications
- Developer: OpenAI
- Context window: 128K tokens
- Max output: 16.4K tokens
- Input modalities: file, image, text
- Output modalities: text
- Input price: $1.25 per 1M tokens
- Output price: $10.00 per 1M tokens
- Knowledge cutoff: —
- Supported parameters: max_completion_tokens, max_tokens, response_format, seed, structured_outputs, tool_choice, tools
Use GPT-5.1 Chat with PromptLayer
PromptLayer lets teams manage, evaluate, and observe prompts that run on GPT-5.1 Chat alongside every other model in their stack. Version prompts, run evals across models, and ship safe rollouts from the same dashboard.
Ready to try it yourself? Sign up for PromptLayer and start managing your prompts in minutes.