How much does GPT-5.1-Codex-Mini cost?

$0.25 per million input tokens and $2 per million output tokens at list price, with cached input at $0.03. The cheapest route is $0.25 in and $2 out. Hoodgen bills in credits (1 credit = Rs 0.10) and shows the estimate before you send.

What is the context window of GPT-5.1-Codex-Mini?

400,000 input tokens with up to 128,000 output tokens.

Is GPT-5.1-Codex-Mini good for coding?

It supports function calling and structured outputs, which agentic coding needs. It handles everyday coding and short refactors well.

Does GPT-5.1-Codex-Mini accept images, audio or files?

It accepts image, text and returns text. Drop an image into the Hoodgen composer and ask about it directly.

How fast is GPT-5.1-Codex-Mini?

Artificial Analysis does not publish latency for this release.

What is the Artificial Analysis score of GPT-5.1-Codex-Mini?

Artificial Analysis does not publish an Intelligence Index for this release, so no score is claimed.

How do I use GPT-5.1-Codex-Mini on Hoodgen?

Open Chat, pick GPT-5.1-Codex-Mini in the model menu and send a prompt. No API key, no card, paid in credits. It is also selectable inside Coding, Writer and the other tools.

OpenAICodingReleased 13 November 2025

GPT-5.1-Codex-Mini pricing, context and benchmark

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

Chat with GPT-5.1-Codex-Mini

400K

Input context

128K

Output context

$0.25

Official input

Official output

n/a

AA index

01 · Model Overview

Everything that matters, in one table

Context, pricing, cache, modalities and tooling, from the model registry and Artificial Analysis.

Model	GPT-5.1-Codex-Mini
Model ID	openai/gpt-5.1-codex-mini
Provider	OpenAI
Release date	13 November 2025
Status	Generally available
Input context	400,000 tokens
Output context	128,000 tokens
Official input pricing	$0.25 per 1M tokens
Official output pricing	$2 per 1M tokens
Cache read pricing	$0.03 per 1M tokens
Market input pricing	$0.25 per 1M (cheapest route)
Market output pricing	$2 per 1M (cheapest route)
Reasoning tokens	Billed as output at $2 per 1M
Input modalities	image · text
Output modalities	text
Reasoning control	Yes, effort levels exposed
Tool support	Functions, tool choice, structured outputs
Tokenizer	GPT
Provider routes	1 endpoint
Artificial Analysis index	Not published
Speed	Not published
Knowledge cutoff	Not publicly stated

Input and output support

Modality	Input	Output	Billed at
Text	✓ yes	✓ yes	$0.25 in
Image	✓ yes	no	$0.25 in
Audio	no	no	not supported
Video	no	no	not supported
File (PDF)	no	no	not supported

02 · Overview

What is GPT-5.1-Codex-Mini?

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

GPT-5.1-Codex-Mini carries a 400K token window, uses the GPT tokenizer and is served by OpenAI. On Hoodgen it sits in the Coding tier of the model menu next to its siblings, so you can switch mid conversation without losing the thread.

03 · Release

Release and what changed from the previous version

Released13 November 2025

Property	gpt-oss-safeguard-20b	GPT-5.1-Codex-Mini	Change
Released	2025	2025	Same release window
Context	131K	400K	Changed
Max output	66K	128K	Changed
Input price	$0.075	$0.25	Higher
Output price	$0.3	$2	Higher
Input modalities	text	image, text	Unchanged
AA index	n/a	n/a	Newer benchmark run

04 · Capabilities

Features and capabilities

◈

Thinking control

Reasoning effort can be dialled per request, so one model covers deep analysis and fast chat.

⚙

Function calling

Tools, tool choice and parallel calls, which is what agent loops need to act on results.

{ }

Structured outputs

Schema constrained JSON with response_format, so no parse and retry loop in your code.

◉

Vision

Screenshots, charts and photographed documents are read at the text token rate.

⚡

Prompt caching

Cached input costs $0.03 per million instead of $0.25, so stable prefixes get cheaper.

⌁

Seeds

A seed can be pinned so the same prompt is reproducible across test runs.

05 · Reasoning

Thinking and reasoning capabilities

GPT-5.1-Codex-Mini can think before answering and exposes the effort level per request. Reasoning tokens bill as output at $2 per million, and the trace can be returned with include_reasoning.

Level	First token	Cost per task	Best for
Measured	n/a	n/a	Artificial Analysis measures the default reasoning configuration
Low effort	Faster	Lower	Chat, autocomplete, classification
High effort	Slower	Higher	Debugging, planning, multi step agents

07 · Use cases

What can you do with GPT-5.1-Codex-Mini?

Code generation

New modules, tests and migrations from a written spec.

Refactoring

Cross file renames and API migrations with the whole repo in context.

Code review

Diff review with reasons, not just lint output.

Pairing

In editor loops inside the Hoodgen Coding workspace.

08 · Cost levers

Prompt caching and how to cut the bill

Cached input bills at $0.03 per million instead of $0.25. Keep the system prompt and documents first and the changing question last, so every call hits the cache.

09 · Pricing

GPT-5.1-Codex-Mini pricing

Official pricing

List price

$0.25 / 1M in

$2 / 1M out

$0.03 cached input
400K context
image, text input

Cheapest route

$0.25 / 1M in

$2 / 1M out

1 route on OpenRouter
What Hoodgen routes to first
Same model, lower bill

Market pricing, every route

Provider	Tier	Input	Output	Cache read	Uptime 24h
Azure	standard	$0.25	$2	$0.03	100.0%

API pricing and cost calculator

Input tokens per callOutput tokens per callCache hit %Number of calls

Rate	Per call	Total	Credits
Cheapest route	$0.0054	$2.68	2546
List price	$0.0054	$2.68	2546

10 · Developers

API and developer information

Model ID	openai/gpt-5.1-codex-mini
Endpoint	https://openrouter.ai/api/v1/chat/completions
Parameters	include_reasoning · max_completion_tokens · reasoning · reasoning_effort · response_format · seed · structured_outputs · tool_choice · tools · verbosity
Streaming	Yes, server sent events
Modality string	text+image->text
Max prompt tokens	400,000
Max completion tokens	128,000

curl https://openrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer $OPENROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-5.1-codex-mini",
    "messages": [{ "role": "user", "content": "Summarise this document." }],
    "max_tokens": 1024
  }'

11 · Limitations

Model limitations

Text only output	It cannot generate images, audio or video. Pair it with an image model on Hoodgen when you need visuals.
Output cap	128,000 tokens per request. Long deliverables have to be chunked.
Benchmarks not published	Artificial Analysis does not publish an Intelligence Index for this release, so no benchmark score is claimed here.
Knowledge cutoff	The provider does not state a fixed cutoff for every release. Verify very recent events against search.

12 · Comparison

GPT-5.1-Codex-Mini vs other OpenAI models

Model	Context	Input /1M	Output /1M	AA index	Released
GPT-5.1-Codex-Mini	400K	$0.25	$2	n/a	2025
GPT-5.5 Pro	1.05M	$30	$180	n/a	2026
GPT-5.4 Pro	1.05M	$30	$180	n/a	2026
GPT-5.2 Pro	400K	$21	$168	n/a	2025
o3 Pro	200K	$20	$80	n/a	2025
GPT-5 Pro	400K	$15	$120	n/a	2025

13 · Privacy

Privacy and data policy

On Hoodgen, prompts and attachments answer that request and stay in your conversation history so you can reopen it. They are not used to train models.
Requests route through OpenRouter to OpenAI and are covered by that provider's API terms.
Do not paste secrets or personal data you would not send to any hosted model.

14 · FAQ

GPT-5.1-Codex-Mini questions, answered

GPT-5.1-Codex-Mini is a coding model from OpenAI, released 13 November 2025. GPT-5.1-Codex-Mini is a smaller and faster version of GPT-5.1-Codex

✦

Start chatting with GPT-5.1-Codex-Mini

Free to try on Hoodgen AI, with a live credit estimate before every send. No API key, no setup.

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