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GPT-4o mini vs GPT-5 nano

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

Updated

GPT-4o mini specs · GPT-5 nano specs
Verdict by category
  • PriceGPT-5 nano

    GPT-5 nano is roughly 1.5× cheaper on output tokens ($0.40 vs $0.60 per 1M).

  • Context windowGPT-5 nano

    GPT-5 nano accepts 400K tokens vs 128K, 3.1× 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 GPT-4o mini's 0. GPT-5 nano is roughly 1.5× cheaper on output tokens ($0.40 vs $0.60 per 1M). GPT-5 nano accepts 400K tokens vs 128K, 3.1× 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 13 months after GPT-4o mini, which usually means a more recent knowledge cutoff and updated safety post-training. GPT-4o mini is usually picked for customer support and summarization workloads, while GPT-5 nano sees more deployments in cheapest llm and fastest llm. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecGPT-4o miniGPT-5 nano
ProviderOpenAIOpenAI
ReleasedJul 2024Aug 2025
Modalitiestext, visiontext, vision
Context window128K tokens400K tokens
Max output,128K tokens
Input · 1M$0.15 / 1M tokens$0.050 / 1M tokens
Output · 1M$0.60 / 1M tokens$0.40 / 1M tokens
Knowledge cutoff,2024-09
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$1.35 vs $0.750
  • Heavy usage, 1M in / 500k out per day$13.50 vs $7.50
  • RAG workload, 5M in / 200k out per day$26.10 vs $9.90

Light usage, 100k in / 50k out per day: $1.35 vs $0.750 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $13.50 vs $7.50 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $26.10 vs $9.90 per month, model B 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-4o mini$0.045
  • GPT-5 nano$0.025

Benchmarks compared

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

GPT-4o miniGPT-5 nano
  • MMLU82.0
Pick GPT-4o mini if

GPT-4o mini fits when…

  • Cheap
  • Fast
  • Mature
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, 1.5× cheaper than GPT-4o mini on output tokens.
  • Long-context tasks, handles 400K tokens vs 128K for GPT-4o mini.
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-4o mini vs GPT-5.5GPT-5 nano vs GPT-5.5

Frequently asked

  • Is GPT-4o mini or GPT-5 nano cheaper?
    GPT-5 nano is cheaper at $0.40 / 1M tokens per million output tokens, vs $0.60 / 1M tokens for GPT-4o mini.
  • Which has the larger context window?
    GPT-5 nano accepts 400K tokens vs 128K for GPT-4o mini.
  • Is GPT-4o mini or GPT-5 nano better for coding?
    Both GPT-4o mini and GPT-5 nano 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-4o mini and GPT-5 nano released?
    GPT-4o mini was released by OpenAI on 2024-07-18. GPT-5 nano was released by OpenAI on 2025-08-07.
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