GPT-5.1 Codex
GPT-5.1 Codex is OpenAI's language model with a 400K context window and up to 128K output tokens, available from 4 providers, starting at $1.25 / 1M input and $10.00 / 1M output. A GPT-5.1 variant purpose-built for agentic coding tasks in Codex environments, available exclusively via the Responses API.
Capabilities
Input3/5
Text✓
Image✓
Audio·
Video·
PDF✓
Output1/5
Text✓
Image·
Audio·
Video·
Embedding·
Capabilities7/13
Reasoning✓
Adaptive Reasoning·
Function Calling✓
Parallel Function Calling✓
Structured Outputs✓
Native JSON Schema✓
Web Search✓
URL Context·
Computer Use·
Code Execution·
File Search·
Prompt Caching✓
Assistant Prefill·
Pricing by Provider
US Dollar ($)
Per 1M tokens
| Provider | Standard | |||
|---|---|---|---|---|
| Input $ / 1M | Output $ / 1M | Cache Read $ / 1M | Web Search $ / request | |
| $1.25 | $10.00 | $0.125 | N/A | |
| $1.25 | $10.00 | $0.125 | N/A | |
| $1.25 | $10.00 | $0.13 | $0.010 | |
| $1.25 | $10.00 | $0.125 | N/A | |
Cost Calculator
US Dollar ($)
Preset:
Versions
| Version | Released | Context | Input / 1M | Output / 1M | Status |
|---|---|---|---|---|---|
| GPT-5.5 | 1.1M | $5.00 | $30.00 | Available | |
| GPT-5.4 Mini | 1.1M | $0.750 | $4.50 | Available | |
| GPT-5.4 Nano | 1.1M | $0.200 | $1.25 | Available | |
| GPT-5.4 | 1.1M | $2.50 | $15.00 | Available | |
| GPT-5.3 Codex | 400K | $1.75 | $14.00 | Available | |
| GPT-5.2 Codex | 400K | $1.75 | $14.00 | Available | |
| GPT-5.2 | 410K | $1.75 | $14.00 | Available | |
| GPT-5.1 Codex | 400K | $1.25 | $10.00 | Current | |
| GPT-5.1 | 410K | $1.25 | $10.00 | Available | |
| GPT-5.1 Codex Mini | 400K | $0.250 | $2.00 | Available | |
| GPT-5 Codex | 400K | $0.125 | $10.00 | Available |