GPT-5.1

openai/gpt-5.1

Strong coding and agentic model with configurable reasoning. Consider migrating to GPT-5.4.

Specifications

Context Window 400K tokens

Max Output 128K tokens

Latency moderate

Knowledge Cutoff Sep 2024

Training Data Sep 2024

Pricing

Input $1.25 per 1M tokens

Output $10.00 per 1M tokens

Capabilities

text Text generation and understanding

vision Image and visual input processing

tool use Function calling and tool integration

reasoning Advanced multi-step reasoning with chain-of-thought

API Identifiers

Model ID openai/gpt-5.1

Provider API ID gpt-5.1

Usage via Multi-Router

curl https://api.multi-router.ai/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -H "x-mr-router-id: YOUR_ROUTER_ID" \
  -d '{
    "model": "openai/gpt-5.1",
    "messages": [
      {"role": "user", "content": "Hello!"}
    ]
  }'