LLM·Dex

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

    GPT-5 nano is roughly 11.0× cheaper on output tokens ($0.40 vs $4.40 per 1M).

  • Context windowGPT-5 nano

    GPT-5 nano 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.

  • ModalitiesTie

    Both handle text, vision.

  • OpennessTie

    Both are closed-weight, API-only.

On balance GPT-5 nano edges ahead, winning 2 of 5 categories against o4-mini's 0. GPT-5 nano is roughly 11.0× cheaper on output tokens ($0.40 vs $4.40 per 1M). GPT-5 nano 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. Both target the same set of modalities (text, vision), so the deciding factors are price, context, and raw quality. Both are closed-weight, API-only.

GPT-5 nano 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 nano is usually picked for cheapest llm and fastest llm 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 nanoo4-mini
ProviderOpenAIOpenAI
ReleasedAug 2025Apr 2025
Modalitiestext, visiontext, vision
Context window400K tokens200K tokens
Max output128K tokens,
Input · 1M$0.050 / 1M tokens$1.10 / 1M tokens
Output · 1M$0.40 / 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$0.750 vs $9.90
  • Heavy usage, 1M in / 500k out per day$7.50 vs $99.00
  • RAG workload, 5M in / 200k out per day$9.90 vs $191

Light usage, 100k in / 50k out per day: $0.750 vs $9.90 per month, model A comes out ahead. Heavy usage, 1M in / 500k out per day: $7.50 vs $99.00 per month, model A comes out ahead. RAG workload, 5M in / 200k out per day: $9.90 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 nano$0.025
  • 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 nanoo4-mini
  • GPQA,81.4
Pick GPT-5 nano if

GPT-5 nano fits when…

  • Lowest-cost OpenAI model with vision support
  • Fast P99 latency
  • Good enough for routing and classification
  • Cost-sensitive workloads, 11.0× 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.

Frequently asked

  • Is GPT-5 nano or o4-mini cheaper?
    GPT-5 nano is cheaper at $0.40 / 1M tokens per million output tokens, vs $4.40 / 1M tokens for o4-mini.
  • Which has the larger context window?
    GPT-5 nano accepts 400K tokens vs 200K for o4-mini.
  • Is GPT-5 nano or o4-mini better for coding?
    Both GPT-5 nano 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 nano and o4-mini released?
    GPT-5 nano was released by OpenAI on 2025-08-07. o4-mini was released by OpenAI on 2025-04-16.
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