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GPT-5 mini vs o4-mini

A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.

Updated

GPT-5 mini specs · o4-mini specs
Verdict by category
  • PriceGPT-5 mini

    GPT-5 mini is roughly 2.2× cheaper on output tokens ($2.00 vs $4.40 per 1M).

  • Context windowGPT-5 mini

    GPT-5 mini accepts 400K tokens vs 200K, 2.0× the room for long documents and codebases.

  • BenchmarksTie

    No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.

  • ModalitiesGPT-5 mini

    GPT-5 mini supports 3 modalities (text, vision, audio) vs 2 for o4-mini.

  • OpennessTie

    Both are closed-weight, API-only.

On balance GPT-5 mini edges ahead, winning 3 of 5 categories against o4-mini's 0. GPT-5 mini is roughly 2.2× cheaper on output tokens ($2.00 vs $4.40 per 1M). GPT-5 mini accepts 400K tokens vs 200K, 2.0× the room for long documents and codebases.

No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, GPT-5 mini handles text, vision, audio while o4-mini handles text, vision, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.

GPT-5 mini is the newer of the two, released 4 months after o4-mini, which usually means a more recent knowledge cutoff and updated safety post-training. GPT-5 mini is usually picked for code completion and customer support workloads, while o4-mini sees more deployments in reasoning and math. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecGPT-5 minio4-mini
ProviderOpenAIOpenAI
ReleasedAug 2025Apr 2025
Modalitiestext, vision, audiotext, vision
Context window400K tokens200K tokens
Max output128K tokens,
Input · 1M$0.25 / 1M tokens$1.10 / 1M tokens
Output · 1M$2.00 / 1M tokens$4.40 / 1M tokens
Knowledge cutoff2024-092024-06
Open weightsNoNo
API availableYesYes

Pricing at scale

What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.

  • Light usage, 100k in / 50k out per day$3.75 vs $9.90
  • Heavy usage, 1M in / 500k out per day$37.50 vs $99.00
  • RAG workload, 5M in / 200k out per day$49.50 vs $191

Light usage, 100k in / 50k out per day: $3.75 vs $9.90 per month, model A comes out ahead. Heavy usage, 1M in / 500k out per day: $37.50 vs $99.00 per month, model A comes out ahead. RAG workload, 5M in / 200k out per day: $49.50 vs $191 per month, model A comes out ahead.

Price calculator

Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.

  • GPT-5 mini$0.125
  • o4-mini$0.330

Benchmarks compared

Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.

GPT-5 minio4-mini
  • GPQA,81.4
Pick GPT-5 mini if

GPT-5 mini fits when…

  • Excellent price-quality ratio for production workloads
  • Fast first-token latency
  • Same tool-use API surface as flagship
  • Cost-sensitive workloads, 2.2× cheaper than o4-mini on output tokens.
  • Long-context tasks, handles 400K tokens vs 200K for o4-mini.
Pick o4-mini if

o4-mini fits when…

  • Strong reasoning at mid-tier price
  • Fast for a thinking model
  • Solid tool-use
Don't want either?

Consider GPT-5.5

OpenAI's mid-cycle GPT-5 refresh, improved reasoning, tool use, and multimodal grounding over the 2025 launch.

See GPT-5.5 specsGPT-5 mini vs GPT-5.5o4-mini vs GPT-5.5

Frequently asked

  • Is GPT-5 mini or o4-mini cheaper?
    GPT-5 mini is cheaper at $2.00 / 1M tokens per million output tokens, vs $4.40 / 1M tokens for o4-mini.
  • Which has the larger context window?
    GPT-5 mini accepts 400K tokens vs 200K for o4-mini.
  • Is GPT-5 mini or o4-mini better for coding?
    Both GPT-5 mini and o4-mini are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.
  • Are either of these models open source?
    Neither model ships open weights, both are accessible only via their respective providers' APIs.
  • When were GPT-5 mini and o4-mini released?
    GPT-5 mini was released by OpenAI on 2025-08-07. o4-mini was released by OpenAI on 2025-04-16.
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