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Gemini 3 Flash vs GPT-4o

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

Updated

Gemini 3 Flash specs · GPT-4o specs
Verdict by category
  • PriceGPT-4o

    GPT-4o publishes pricing ($10.00 / 1M output tokens) while Gemini 3 Flash does not.

  • Context windowGemini 3 Flash

    Gemini 3 Flash accepts 1.0M tokens vs 128K, 8.2× 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.

  • ModalitiesGemini 3 Flash

    Gemini 3 Flash supports 4 modalities (text, vision, audio, video) vs 3 for GPT-4o.

  • OpennessTie

    Both are closed-weight, API-only.

On balance Gemini 3 Flash edges ahead, winning 2 of 5 categories against GPT-4o's 1. GPT-4o publishes pricing ($10.00 / 1M output tokens) while Gemini 3 Flash does not. Gemini 3 Flash accepts 1.0M tokens vs 128K, 8.2× 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, Gemini 3 Flash handles text, vision, audio, video while GPT-4o handles text, vision, audio, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.

Gemini 3 Flash is the newer of the two, released 19 months after GPT-4o, which usually means a more recent knowledge cutoff and updated safety post-training. Gemini 3 Flash is usually picked for rag and summarization workloads, while GPT-4o sees more deployments in chatbots and vision. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.

Side-by-side specs

SpecGemini 3 FlashGPT-4o
ProviderGoogleOpenAI
ReleasedDec 2025May 2024
Modalitiestext, vision, audio, videotext, vision, audio
Context window1.0M tokens128K tokens
Max output65.5K tokens,
Input · 1MPricing not published$2.50 / 1M tokens
Output · 1MPricing not published$10.00 / 1M tokens
Knowledge cutoff2025-012023-10
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, vs $22.50
  • Heavy usage, 1M in / 500k out per day, vs $225
  • RAG workload, 5M in / 200k out per day, vs $435

Light usage, 100k in / 50k out per day: pricing not directly comparable (one or both models are missing public per-token rates). Heavy usage, 1M in / 500k out per day: pricing not directly comparable (one or both models are missing public per-token rates). RAG workload, 5M in / 200k out per day: pricing not directly comparable (one or both models are missing public per-token rates).

Price calculator

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

  • Gemini 3 FlashPricing unavailable
  • GPT-4o$0.750

Benchmarks compared

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

Gemini 3 FlashGPT-4o
  • MMLU,88.7
  • HumanEval,90.2
Pick Gemini 3 Flash if

Gemini 3 Flash fits when…

  • 1M-token context at mid-tier price
  • Very fast, good for interactive UX
  • Strong vision support
  • Long-context tasks, handles 1.0M tokens vs 128K for GPT-4o.
  • Multimodal needs covering video.
Pick GPT-4o if

GPT-4o fits when…

  • Native multimodal
  • Mature SDK and tooling
Don't want either?

Consider Gemini 3 Pro

Google's late-2025 flagship, set new benchmarks on long-context, vision, and reasoning at competitive pricing.

See Gemini 3 Pro specsGemini 3 Flash vs Gemini 3 ProGPT-4o vs Gemini 3 Pro

Frequently asked

  • Is Gemini 3 Flash or GPT-4o cheaper?
    Per-token pricing isn't published for at least one of these models, check each model's spec page for current rates.
  • Which has the larger context window?
    Gemini 3 Flash accepts 1.0M tokens vs 128K for GPT-4o.
  • Is Gemini 3 Flash or GPT-4o better for coding?
    Both Gemini 3 Flash and GPT-4o 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 Gemini 3 Flash and GPT-4o released?
    Gemini 3 Flash was released by Google on 2025-12-09. GPT-4o was released by OpenAI on 2024-05-13.
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