GPT-5.1-Codex by GitHub Copilot — Specs, Pricing & Capabilities | whichllm

Model ID gpt-5.1-codex

Provider GitHub Copilot

Family gpt-codex

Status -

Knowledge Cutoff 2024-09-30

Release Date 2025-11-13

Input Modalities text, image

Output Modalities text

Context Window 400000

Input Limit 128000

Output Limit 128000

Tool Calling Yes

Reasoning Yes

Structured Output -

Temperature Control No

Open Weights No

Input Cost / 1M tokens -

Output Cost / 1M tokens -

Reasoning Cost / 1M tokens -

Cache Read Cost / 1M tokens -

Cache Write Cost / 1M tokens -