# GPT-5.1 Chat: AI model fact sheet

- **Provider:** openai
- **Released:** 2025-11-13
- **Context window:** 128,000 tokens
- **API pricing:** $1.25 / 1M input, $10.00 / 1M output
- **OpenRouter ID:** openai/gpt-5.1-chat
- **Capabilities:** conversation, reasoning, code-generation, analysis

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.

## Benchmarks

| Benchmark | Score |
| --- | --- |
| SWE-bench Verified | 76.3% |

Source: real side-by-side outputs, pricing and specs at https://rival.tips/models/gpt-5.1-chat