Mistral: Ministral 3 8B 2512 (batch) vs OpenAI: GPT-5.1-Codex-Mini

Neither wins outright: Mistral: Ministral 3 8B 2512 (batch) is the pick when cost matters at scale, OpenAI: GPT-5.1-Codex-Mini when you need to fit long inputs in one request.

Key numbers

SpecMistral: Ministral 3 8B 2512 (batch)OpenAI: GPT-5.1-Codex-Mini
ProviderMistral AIOpenAI
Input price (per 1M tokens)$0.07$0.25
Output price (per 1M tokens)$0.07$2.00
Blended price (3:1 input/output)$0.07$0.69
Cheaper than … of all models we track84%47%
Context window262K tokens (~393 pages)400K tokens (~600 pages)
Larger context than … of all models48%63%
Max output per response210K tokens (~157,300 words)128K tokens (~96,000 words)
Input typestext, imageimage, text
Output typestexttext
Free variantNoNo
Listed since2025-12-022025-11-13
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What it costs for real workloads

Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.

Workload (per month)Mistral: Ministral 3 8B 2512 (batch)OpenAI: GPT-5.1-Codex-MiniDifference
Customer-support chatbot
50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens)
$7.13$58.75Mistral: Ministral 3 8B 2512 (batch) saves $51.63
RAG search over documents
20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens)
$9.75$50.00Mistral: Ministral 3 8B 2512 (batch) saves $40.25
Coding / tool-using agent
2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens)
$9.90$54.00Mistral: Ministral 3 8B 2512 (batch) saves $44.10
Batch summarisation
10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens)
$6.45$32.00Mistral: Ministral 3 8B 2512 (batch) saves $25.55
Long-document analysis
500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens)
$3.82$14.50Mistral: Ministral 3 8B 2512 (batch) saves $10.68

Capabilities side by side

CapabilityMistral: Ministral 3 8B 2512 (batch)OpenAI: GPT-5.1-Codex-MiniWhat it lets you do
Tool / function calling✓ Yes✓ Yescall your APIs and run agent loops
Structured output (JSON schema)✓ Yes✓ Yesreturn JSON that validates against your schema
Reasoning / thinking mode—✓ Yesspend extra tokens thinking before answering hard problems
Image input✓ Yes✓ Yesread screenshots, charts and scanned pages
Audio input——take speech or audio directly
File / PDF input——accept documents without your own parsing step
Image output——generate images, not just text
Built-in web search—✓ Yesanswer from live web results
Seed (reproducible sampling)✓ Yes✓ Yesrepeat a generation for tests and evals
Log-probabilities——read token confidence for classification and scoring

From each model's published parameters and input/output types. “—” means not advertised, not proven absent.

Price history

DateModelInput / 1MOutput / 1M
2026-09-10Mistral: Ministral 3 8B 2512 (batch)$0.07$0.07

Which should you choose?

Choose Mistral: Ministral 3 8B 2512 (batch) if…

  • cost matters at scale — it is 89% cheaper on a typical 3:1 input/output mix ($7.13 vs $58.75 a month for 50,000 support chats)
  • you generate long outputs in one go — up to 210K tokens (about 157,300 words) per response

Choose OpenAI: GPT-5.1-Codex-Mini if…

  • you need to fit long inputs in one request — 400K tokens is roughly 600 pages, against 393
  • you need reasoning / thinking mode — to spend extra tokens thinking before answering hard problems; Mistral: Ministral 3 8B 2512 (batch) does not advertise it
  • you need built-in web search — to answer from live web results; Mistral: Ministral 3 8B 2512 (batch) does not advertise it

Frequently asked questions

Is Mistral: Ministral 3 8B 2512 (batch) better than OpenAI: GPT-5.1-Codex-Mini?

Neither wins outright: Mistral: Ministral 3 8B 2512 (batch) is the pick when cost matters at scale, OpenAI: GPT-5.1-Codex-Mini when you need to fit long inputs in one request. In short: Mistral: Ministral 3 8B 2512 (batch) when cost matters at scale, you generate long outputs in one go; OpenAI: GPT-5.1-Codex-Mini when you need to fit long inputs in one request, you need reasoning / thinking mode, you need built-in web search.

Which is cheaper, Mistral: Ministral 3 8B 2512 (batch) or OpenAI: GPT-5.1-Codex-Mini?

Mistral: Ministral 3 8B 2512 (batch) is cheaper: $0.07 vs $0.69 per 1M tokens at a typical 3:1 input/output mix, 89% less. For 50,000 support conversations a month that is $7.13 against $58.75.

How much do Mistral: Ministral 3 8B 2512 (batch) and OpenAI: GPT-5.1-Codex-Mini cost per million tokens?

Mistral: Ministral 3 8B 2512 (batch) costs $0.07 per 1M input tokens and $0.07 per 1M output tokens; OpenAI: GPT-5.1-Codex-Mini costs $0.25 input and $2.00 output. Output tokens are billed separately, so long answers shift the gap.

Which has the bigger context window, Mistral: Ministral 3 8B 2512 (batch) or OpenAI: GPT-5.1-Codex-Mini?

OpenAI: GPT-5.1-Codex-Mini: 400K tokens, about 600 pages, against 262K (about 393 pages) for Mistral: Ministral 3 8B 2512 (batch).

Do Mistral: Ministral 3 8B 2512 (batch) and OpenAI: GPT-5.1-Codex-Mini support function calling and JSON output?

Tool calling — Mistral: Ministral 3 8B 2512 (batch): yes, OpenAI: GPT-5.1-Codex-Mini: yes. JSON-schema structured output — Mistral: Ministral 3 8B 2512 (batch): yes, OpenAI: GPT-5.1-Codex-Mini: yes.

Can Mistral: Ministral 3 8B 2512 (batch) or OpenAI: GPT-5.1-Codex-Mini read images?

Yes, both accept image input.

Is Mistral: Ministral 3 8B 2512 (batch) or OpenAI: GPT-5.1-Codex-Mini free to use?

No free variant is listed for either; both are pay-per-token.

What is the maximum output length of Mistral: Ministral 3 8B 2512 (batch) and OpenAI: GPT-5.1-Codex-Mini?

Mistral: Ministral 3 8B 2512 (batch) can write up to 210K tokens (about 157,300 words) per response; OpenAI: GPT-5.1-Codex-Mini up to 128K (about 96,000 words).

When were Mistral: Ministral 3 8B 2512 (batch) and OpenAI: GPT-5.1-Codex-Mini released?

Mistral: Ministral 3 8B 2512 (batch) was listed on 2025-12-02; OpenAI: GPT-5.1-Codex-Mini on 2025-11-13.

Has the price of Mistral: Ministral 3 8B 2512 (batch) or OpenAI: GPT-5.1-Codex-Mini changed?

Mistral: Ministral 3 8B 2512 (batch): input price cut 50% ($0.15 → $0.07/1M), output price cut 50% ($0.15 → $0.07/1M) on 2026-09-10. OpenAI: GPT-5.1-Codex-Mini: price unchanged since we started tracking it on 2026-03-10.

About the two models

Compare Mistral: Ministral 3 8B 2512 (batch) with other models

Compare OpenAI: GPT-5.1-Codex-Mini with other models

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