GPT-5.1

OpenAI's flagship model for coding and agentic tasks with configurable reasoning.

Configurable ReasoningCodingTool Use

Context Window

400,000

GPT-5.1

Max Output

128,000

1M tokens

Input

$1.25

Output

$10

Model Codegpt-5.1

Playground

Model Code

gpt-5.1

Reference inputs

Reference Images0/5

Click or drag

Enter your prompt here...

Output

No output yet

Pricing

Plan	Context Window	Max Output	Input	Output	Cache Write	Cache Read
GPT-5.1	400,000	128,000	$1.25	$10	-	$0.125

Official OpenAI pricing for GPT-5.1.

Cached input pricing applies to reused prompt tokens.

Cache read or cached input pricing applies to reused prompt tokens.

README

GPT-5.1 is OpenAI's flagship GPT-5-family model for complex coding and agentic work, adding better steerability, lower-latency reasoning options, and stronger support for tool-rich workflows.

OpenAI describes GPT-5.1 as its flagship model for coding and agentic tasks with configurable reasoning and non-reasoning effort.
Compared with GPT-5, GPT-5.1 adds a `none` reasoning setting for lower latency, stronger steerability, and workflow improvements for tool-heavy coding use cases.
It is a strong fit for complex coding systems, broad-world-knowledge tasks, and multi-step API workflows that need more control over latency versus reasoning depth.

API

Use the API docs for request format, parameters, and integration details.

OpenAI's flagship model for coding and agentic tasks with configurable reasoning.

Model Code

gpt-5.1

View API Docs

API

Endpoint

POST /v1/chat/completions

Authentication

Authorization: Bearer YOUR_REACH_API_KEY
Content-Type: application/json

Example

curl -X POST "https://direct.reachapi.ai/v1/chat/completions" \
  -H "Authorization: Bearer YOUR_REACH_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "YOUR_MODEL_ID",
    "messages": [
      {
        "role": "user",
        "content": "Introduce ReachAPI in one sentence."
      }
    ],
    "temperature": 0.2
  }'

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