OpenAI: GPT-5.1-Codex-Mini

openai/gpt-5.1-codex-mini

GPT-5.1-Codex-Mini is a smaller and faster version of GPT-5.1-Codex

Modalities

In / out price

$0.25 / $2 per 1M

Context

400K

Released

Nov 13, 2025

Why use GPT-5.1-Codex-Mini

List prices via OpenRouter, checked daily. Real cost depends on the provider and on reasoning tokens.

Pick a task, set how often you run it, and compare what it costs on each model.

TaskInput tokens≈ 602 wordsOutput tokens≈ 1,504 wordsRuns per month

Input served from cache: 0%Repeated prompts (same instructions or document) are billed at the cheaper cache-read price where the model supports it.

Model	Per run	Per month	Per 1,000 runs
OpenAI: GPT-5.1-Codex-Mini	$0.0042	$4.20	$4.20

Estimates from list prices via OpenRouter; real bills vary by provider and reasoning tokens.

Each square is about one page (500 words). Colored squares are your content; grey squares are free space in the model's context window.

Your content

Total: about 120,000 tokens (≈ 90,226 words). Token counts are estimates.

Models

Zoom (square size): 6pxZoom out to see a whole million-token window at once.

400,000 tokens ≈ 602 pages

Fits: uses 30% of the window (room for 3× this much).

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