GPT-5.3-codex
gpt-5.3-codex
OpenAI · chat · api
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Intelligence
Context
400K
Max output
—
Input $/1M
$1.75
Output $/1M
$14.00
Modalities
text
Released
08 Feb 2026
Intelligence Index via Artificial Analysis · 0–100, higher is better
AI summary
● machine-written
GPT-5.3-Codex released with 400K context window and coding focus
GPT-5.3-Codex is OpenAI's text-based API model for coding and professional work, released February 24, 2026. It supports a 400K token context window and is positioned as a mid-range option in OpenAI's lineup for developers building with code generation capabilities.
What's new
- Released February 24, 2026
- 400K token context window
- Pricing: $1.75 per million input tokens, $14.00 per million output tokens
- GPQA benchmark score of 91.5 (98th percentile)
Best for
Code generation and completionProfessional development tasksLonger context coding workflows