ZMIME
Comparison · 2 models · Updated Oct 4, 2026

Gemini 2.0 Flash vs o3-pro

Too close to call on our weighted score (o3-pro 68, Gemini 2.0 Flash 65). The right pick depends on what you value most.

  1. Google

    Gemini 2.0 Flash

    Released Dec 11, 2024

    65/100
    • ECI134.7
    • Price—
    • Context1.05M
    Full specs Remove Gemini 2.0 Flash

  2. OpenAI

    o3-pro

    Released Jun 10, 2025

    68/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
    Full specs Remove o3-pro

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Too close to call

It is close. Our weighted score puts them within 3 points (o3-pro 68/100, Gemini 2.0 Flash 65/100), so choose by what matters most for your work: o3-pro for raw capability and Gemini 2.0 Flash for long inputs. The score weighs capability 67%, inputs & features 20%, context window 13%.

  • Capabilityo3-proCapabilities Index (ECI): o3-pro 147.4 · Gemini 2.0 Flash 134.7
  • Lowest priceo3-proo3-pro $35.00 per 1M tokens (3:1 blend) · Gemini 2.0 Flash unpriced
  • Longest contextGemini 2.0 FlashGemini 2.0 Flash 1,048,576 · o3-pro 200,000 tokens
  • Widest inputsGemini 2.0 FlashGemini 2.0 Flash: Text, Images, PDFs, Audio, Video · o3-pro: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGemini 2.0 Flasho3-pro
CapabilityCapabilities Index (ECI)67%5975
Inputs & features20%9070
Context window13%6132
Overall100%65/10068/100

Left out because at least one model lacks the data: price. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

Gemini 2.0 Flash vs o3-pro specifications side by side
SpecificationGemini 2.0 FlashGoogleo3-proOpenAI
Capability
Capabilities Index (ECI)134.7147.4 (best)
ECI rank#116 of 148#60 of 148 (best)
Price per million tokens
Input—$20.00
Output—$80.00
Cached input——
Blended (3:1)—$35.00
Long-context rate—Same rate
Price source—Official OpenAI API
Limits
Context window1,048,576 tokens (best)200,000 tokens
Max output8,192 tokens100,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioYesNo
VideoYesNo
ReasoningNoYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model ID—o3-pro
API providers—6
ReleasedDec 11, 2024Jun 10, 2025
Knowledge cutoffJun 2024May 2024
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • Gemini 2.0 Flash—
  • o3-pro$360.00
04 — Questions

Which should you choose?

Which is better: Gemini 2.0 Flash or o3-pro?

It is close. Our weighted score puts them within 3 points (o3-pro 68/100, Gemini 2.0 Flash 65/100), so choose by what matters most for your work: o3-pro for raw capability and Gemini 2.0 Flash for long inputs. The score weighs capability 67%, inputs & features 20%, context window 13%.

Which is cheaper, Gemini 2.0 Flash or o3-pro?

o3-pro is cheaper at $20.00 input / $80.00 output per million tokens (official OpenAI API price). . At a typical mix of three input tokens to one output token, that is $35.00 per million tokens for o3-pro versus . Gemini 2.0 Flash has no published per-token price.

Which scores higher on benchmarks?

o3-pro scores higher on the Capabilities Index (ECI): o3-pro 147.4 (#60 of 148) and Gemini 2.0 Flash 134.7 (#116 of 148). Their confidence ranges do not overlap (145.8–149.7 vs 124.3–136.7), so the gap is a real one.

Which is better for coding?

There are no published SWE-bench Verified results for Gemini 2.0 Flash and o3-pro yet, so there is no like-for-like coding score. On overall capability, o3-pro leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

Gemini 2.0 Flash has the largest context window at 1,048,576 tokens, against 200,000 for o3-pro. Maximum output per response: Gemini 2.0 Flash up to 8,192, o3-pro up to 100,000 tokens.

Which can read images, PDFs, audio or video?

Gemini 2.0 Flash accepts text, images, PDFs, audio and video; o3-pro accepts text and images. Gemini 2.0 Flash handles the widest range of inputs.

Are any of these open source?

No. Gemini 2.0 Flash and o3-pro are proprietary and only available through APIs and apps.

Which is newer?

o3-pro is the newest, released Jun 10, 2025. Gemini 2.0 Flash came out Dec 11, 2024. Knowledge cutoff: Gemini 2.0 Flash Jun 2024, o3-pro May 2024.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.

05 — Keep comparing

Related comparisons