GPT-4o mini vs GPT-5.4 Nano

OpenAI · US  |  OpenAI · US · Updated June 2026

Quick verdict

Both are OpenAI models. GPT-5.4 Nano is the newer, generally stronger default; reach for GPT-4o mini when its lower price or a specific cost or latency profile matters more than the latest capabilities.

GPT-4o mini and GPT-5.4 Nano are both OpenAI models, so the real question is not which lab to trust but which tier fits your workload and budget. GPT-4o mini is openAI's budget small multimodal model — cheap, fast text-and-vision intelligence that outscored peer small models like Gemini 1.5 Flash and Claude 3 Haiku on MMLU and HumanEval at launch. GPT-5.4 Nano is openAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.

Key differences at a glance

Side-by-side specs

SpecGPT-4o miniGPT-5.4 Nano
ProviderOpenAI (US) OpenAI (US)
ReleasedJuly 18, 2024 March 17, 2026
Context window128K (~192 pages) 400K (~600 pages)
Price (in/out)$0.15/$0.6 per 1M tokens $0.2/$1.25 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Very low cost per token for its capability tier

GPT-4o mini

At $0.15/$0.6 per 1M tokens it undercuts GPT-5.4 Nano ($0.2/$1.25 per 1M tokens), and that gap compounds at volume.

Strong coding for a small model (87.2% HumanEval)

GPT-4o mini

GPT-5.4 Nano is comparatively weak here — a nano tier — not built for hard reasoning or frontier coding

Leading MMLU among peer small models (82%)

GPT-4o mini

OpenAI's budget small multimodal model — cheap, fast text-and-vision intelligence that outscored peer small models like Gemini 1.5 Flash and Claude 3 Haiku on MMLU and HumanEval at launch — and it runs cheaper at $0.15/$0.6 per 1M tokens.

Cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

GPT-5.4 Nano

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning — and it carries the larger 400K context.

Classification, extraction, ranking and sub-agent execution at scale

GPT-5.4 Nano

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning — and it is the newer of the two.

A 400K context in the smallest, fastest GPT-5.4 variant

GPT-5.4 Nano

Its 400K window holds about 3.1× more than GPT-4o mini's 128K in a single prompt.

Lowest cost at scale

GPT-4o mini

At $0.15/$0.6 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

GPT-5.4 Nano

Its 400K window is about 3.1× larger than GPT-4o mini's 128K, fitting roughly 600 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

GPT-4o mini

At $0.15/$0.6 per 1M tokens it undercuts GPT-5.4 Nano, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-5.4 Nano

Larger 400K window fits more in one prompt.

Anyone whose priority is very low cost per token for its capability tier

GPT-4o mini

It is specifically built for that.

Anyone whose priority is cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

GPT-5.4 Nano

That is its strongest area.

GPT-4o mini: where it fits

OpenAI's budget small multimodal model — cheap, fast text-and-vision intelligence that outscored peer small models like Gemini 1.5 Flash and Claude 3 Haiku on MMLU and HumanEval at launch. Released July 18, 2024 by OpenAI, it is built for very low cost per token for its capability tier, strong coding for a small model (87.2% HumanEval), leading MMLU among peer small models (82%), and text and image (vision) understanding in the API.

Its trade-offs are real: only 128K context with an October 2023 knowledge cutoff, and weaker on hard reasoning and coding than frontier models. At $0.15 in / $0.6 out per million tokens, it sits in the budget price band.

GPT-5.4 Nano: where it fits

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. Released March 17, 2026 by OpenAI, it is built for cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work, classification, extraction, ranking and sub-agent execution at scale, a 400K context in the smallest, fastest GPT-5.4 variant, and text and image input for cheap multimodal pipelines.

Its trade-offs: a nano tier — not built for hard reasoning or frontier coding, no published SWE-Bench Verified score (OpenAI reported SWE-Bench Pro instead), outclassed by GPT-5.4 and GPT-5.4 Mini whenever a task needs real depth, and image input only — no audio or video. At $0.2 in / $1.25 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Because GPT-4o mini and GPT-5.4 Nano come from the same lab (OpenAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. GPT-5.4 Nano is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to GPT-5.4 Nano and drop down only with a concrete reason.

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Frequently asked questions

Is GPT-4o mini or GPT-5.4 Nano better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, GPT-4o mini leans toward very low cost per token for its capability tier while GPT-5.4 Nano leans toward cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, GPT-4o mini or GPT-5.4 Nano?

GPT-4o mini is cheaper — $0.15/$0.6 per 1M tokens vs $0.2/$1.25 per 1M tokens, roughly 1.3× apart on input.

Which has the bigger context window?

GPT-5.4 Nano — 400K vs 128K, about 3.1× larger. Useful only if the model actually reasons over the full window, which not all do.

Should I upgrade from GPT-4o mini to GPT-5.4 Nano?

Since both are OpenAI models, the newer one (GPT-5.4 Nano) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, GPT-4o mini or GPT-5.4 Nano?

GPT-5.4 Nano — released March 17, 2026, about 20 months after GPT-4o mini.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.