Compare / Mistral Medium 3 vs GPT-5.1

Mistral Medium 3 vs GPT-5.1

Which is cheaper, which is more capable, and which does better at each kind of work, from 16 results on 3 sources that measured both models.

Mistral Medium 3
Mistral · profile
GPT-5.1
OpenAI · profile
Results compared
16
Shared sources
3

Mistral Medium 3 or GPT-5.1? The short answer

  • Mistral Medium 3 is cheaper: $0.80 against $3.44 per million tokens, 4.3 times less.
  • GPT-5.1 scores higher on the Artificial Analysis Intelligence Index: 24.7 against 9.0.
  • On our business benchmarks, Mistral Medium 3 ranks higher for agents and tool use.
  • On our business benchmarks, GPT-5.1 ranks higher for reasoning and knowledge and writing.

At a glance

Mistral Medium 3GPT-5.1
Price per million tokens$0.40 in · $2.00 out$1.25 in · $10.00 out
Blended (3 in : 1 out)$0.80$3.44
Cheapest host, blended$0.80 (Mistral)$1.72 (OpenAI)
Intelligence Index9.024.7
Spring Prompt overall––
Output speed, tokens a second––
Context window131,072 tokens400,000 tokens
WeightsClosedClosed
Developer based inFrancethe US

Prices are the developer's list price where we have read it, otherwise the typical host on OpenRouter; see every model's price. Intelligence and speed from Artificial Analysis.

Which is better for what

Each model's rank among models available today, for each kind of work, from our own benchmarks and licensed sources. The better rank is in green.

Use caseMistral Medium 3GPT-5.1
Agents and tool useMulti-step tasks with tools: support desks, coding agents, function calls 81 of 161 82 of 161
Reasoning and knowledgeHard questions across science, maths and general knowledge 160 of 195 66 of 195
WritingWhat people prefer in blind comparisons, and judged writing quality 127 of 187 52 of 187
Sticking to the factsSummarising without inventing things, and factual answers not measured 62 of 153

Every shared result

BenchmarkMetricMistral Medium 3GPT-5.1
Arena (formerly LMArena)reportedBusiness, management and financeArena rating 1,3871,448
Arena (formerly LMArena)reportedCreative writingArena rating 1,3641,428
Arena (formerly LMArena)reportedExpert promptsArena rating 1,3791,482
Arena (formerly LMArena)reportedInstruction followingArena rating 1,3661,450
Arena (formerly LMArena)reportedOverallArena rating 1,3871,456
Arena (formerly LMArena)reportedWriting, literature and languageArena rating 1,3701,437
Artificial AnalysisreportedArtificial Analysis Intelligence Indexindex score 9.0024.7
Artificial AnalysisreportedGPQA Diamond% of questions 57.8%87.3%
Artificial AnalysisreportedHumanity's Last Exam% of questions 4.1%28.5%
Artificial AnalysisreportedIFBench% of instructions 39.3%72.9%
Artificial AnalysisreportedLong-context reasoning (AA-LCR)% of questions 31.3%80.0%
Artificial AnalysisreportedTerminal-Bench Hard% of tasks 3.8%45.5%
Artificial AnalysisreportedΤ²-bench telecom% of tasks 24.3%81.9%
UGI LeaderboardreportedRequested-length error% off the requested word count 20.0%113.0%
UGI LeaderboardreportedStyle adherencescore from 0 to 1 0.350.38
UGI LeaderboardreportedWriting scorescore out of 100 32.655.8

Bold green marks the better value on that metric. Where a source reports ranges that overlap, the difference may not be meaningful; see the benchmark page for ranges.

Quick answers

Is Mistral Medium 3 better than GPT-5.1?

It depends on the task. Among models available today, on our benchmarks and licensed sources, Mistral Medium 3 ranks higher for agents and tool use; GPT-5.1 ranks higher for reasoning and knowledge and writing.

Which is cheaper, Mistral Medium 3 or GPT-5.1?

Mistral Medium 3 costs $0.80 per million tokens (three input to one output), against $3.44 for GPT-5.1.

Run Mistral Medium 3 and GPT-5.1 on your own prompt

Benchmarks aren't your data. Try both side by side in the playground, with the cost of every answer.