CorX Labs

Head to head

o4-mini vs GPT-5 mini

o4-mini from OpenAI against GPT-5 mini from OpenAI — specification, price and every benchmark both makers have published, in one table.

Benchmarks

GPT-5 mini leads

GPT-5 mini wins 2 of the 3 benchmarks both models report, o4-mini wins 1, though the gaps are small. The average gap across shared tests is 1.8 points.

Price

GPT-5 mini is cheaper

On a 3:1 input-to-output mix, GPT-5 mini costs $0.688 per million tokens against $1.93 for o4-mini — about 2.8× less. Remember that a reasoning model bills its thinking as output, so cost per answer can diverge much further than cost per token.

What actually differs

  • GPT-5 mini takes 400K tokens of context against 200K — 2.0× more room for long documents or a large codebase.

Scorecard

Which is better at what

Maths, coding, reasoning and the rest — one line each, averaged over the benchmarks both models actually report.

Which model scores higher in each capability category, averaged over the benchmarks all of them report.
Categoryo4-miniGPT-5 miniBetter at this
ReasoningGPQA Diamond81.4%82.3%GPT-5 mini+0.9
MathsAIME 202592.7%91.1%o4-mini+1.6
CodingSWE-bench Verified68.1%71.0%GPT-5 mini+2.9
KnowledgeNeither model reports thisNot comparable
MultimodalOnly one model reports thisNot comparable
Instruction followingNeither model reports thisNot comparable
Human preferenceNeither model reports thisNot comparable
Categories wonOut of 3 comparable12GPT-5 mini

Each category averages only the benchmarks every model here reports, so no one is credited for a test the other did not run. A category with no shared test is marked Not comparable rather than guessed at.

Side by side

o4-mini and GPT-5 mini, row by row

Attributeo4-miniOpenAIGPT-5 miniOpenAI
Specification
MakerWho built itOpenAIOpenAI
Released2025-042025-08
ArchitectureNot reportedMoE
Context windowHow much can go in at once200,000 tokens400,000 tokens
Max output100,000 tokens128,000 tokens
InputText, ImageText, Image
ReasoningSpends extra tokens thinking before it answersYesYes
Tool callingYesYes
Knowledge cutoff2024-062024-05
LicenceProprietaryProprietary
Open weightsCan you download and run it yourselfNoNo
Price
Input priceUSD per million tokens in$1.10$0.25
Output priceUSD per million tokens out$4.40$2.00
Cached input$0.275$0.025
Blended 3:1A 3-in-to-1-out million-token mix — a fairer single number than input price alone$1.93$0.688Cheapest
Published benchmarks
GPQA Diamond198 graduate-level physics, chemistry and biology questions written to be Google-proof. PhD holders in the matching field score about 65%.81.4%82.3%Best
AIME 2025The American Invitational Mathematics Examination — 15 problems, integer answers, no partial credit. A standard test of multi-step maths reasoning.92.7%Best91.1%
SWE-bench Verified500 human-validated GitHub issues from real Python repositories. The model must produce a patch that makes the project's own tests pass.68.1%71%Best
MMMUCollege-level questions that require reading charts, diagrams, tables and photographs alongside the text.81.6%Not reported
LinksFull pageFull page
Row verified2026-082026-08

Where these numbers come from

Every score on this page is a published figure, taken from the model's own card, system card, technical report or release post, or from a public leaderboard. CorX Labs did not run these evaluations. Most are self-reported by the lab that built the model, which means they were produced under that lab's own choice of prompt, scaffold and number of attempts — so treat them as a starting point for a shortlist, not as a settled ranking.

A score someone other than the model's maker measured is marked Independent and names its measurer. Those are the stronger numbers on this page — an outside harness has no reason to flatter anyone — and there are not many of them.

Where a figure has not been published, the cell reads Not reported rather than an estimate. Nothing here is inferred, interpolated or guessed. Each model records the month its row was last checked. Full method and caveats.

Questions

o4-mini or GPT-5 mini?

Is o4-mini better than GPT-5 mini?

GPT-5 mini wins 2 of the 3 benchmarks both models report, o4-mini wins 1, though the gaps are small. The average gap across shared tests is 1.8 points.

Which is cheaper, o4-mini or GPT-5 mini?

On a 3:1 input-to-output mix, GPT-5 mini costs $0.688 per million tokens against $1.93 for o4-mini — about 2.8× less. Remember that a reasoning model bills its thinking as output, so cost per answer can diverge much further than cost per token.

What is the difference between o4-mini and GPT-5 mini?

GPT-5 mini takes 400K tokens of context against 200K — 2.0× more room for long documents or a large codebase.