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Gemini 3 Flash vs o3-mini

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 · o3-mini specs
Verdict by category
  • Priceo3-mini

    o3-mini publishes pricing ($4.40 / 1M output tokens) while Gemini 3 Flash does not.

  • Context windowGemini 3 Flash

    Gemini 3 Flash accepts 1.0M tokens vs 200K, 5.2× 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 1 for o3-mini.

  • OpennessTie

    Both are closed-weight, API-only.

On balance Gemini 3 Flash edges ahead, winning 2 of 5 categories against o3-mini's 1. o3-mini publishes pricing ($4.40 / 1M output tokens) while Gemini 3 Flash does not. Gemini 3 Flash accepts 1.0M tokens vs 200K, 5.2× 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 o3-mini handles text, 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 10 months after o3-mini, 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 o3-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

SpecGemini 3 Flasho3-mini
ProviderGoogleOpenAI
ReleasedDec 2025Jan 2025
Modalitiestext, vision, audio, videotext
Context window1.0M tokens200K tokens
Max output65.5K tokens,
Input · 1MPricing not published$1.10 / 1M tokens
Output · 1MPricing not published$4.40 / 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 $9.90
  • Heavy usage, 1M in / 500k out per day, vs $99.00
  • RAG workload, 5M in / 200k out per day, vs $191

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
  • o3-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.

Gemini 3 Flasho3-mini
  • GPQA,79.7
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 200K for o3-mini.
  • Multimodal needs covering vision, audio, video.
Pick o3-mini if

o3-mini fits when…

  • Reasoning at mid-tier cost
  • Fast for a thinking model
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 Proo3-mini vs Gemini 3 Pro

Frequently asked

  • Is Gemini 3 Flash or o3-mini 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 200K for o3-mini.
  • Is Gemini 3 Flash or o3-mini better for coding?
    Both Gemini 3 Flash and o3-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 Gemini 3 Flash and o3-mini released?
    Gemini 3 Flash was released by Google on 2025-12-09. o3-mini was released by OpenAI on 2025-01-31.
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