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Comparison · 3 models · Updated Oct 4, 2026

Gemini 2.0 Flash vs o3-pro vs Claude Opus 4

Too close to call on our weighted score (o3-pro 68, Gemini 2.0 Flash 65, Claude Opus 4 64). 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
  2. OpenAI

    o3-pro

    Released Jun 10, 2025

    68/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
  3. Anthropic

    Claude Opus 4

    Released May 22, 2025

    64/100
    • ECI142.7
    • Price$15.00 / $75.00
    • Context200K
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, Claude Opus 4 64/100), so choose by what matters most for your work: o3-pro for raw capability, Claude Opus 4 on price 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 · Claude Opus 4 142.7 · Gemini 2.0 Flash 134.7
  • Lowest priceClaude Opus 4Claude Opus 4 $30.00 · o3-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 · Claude Opus 4 200,000 tokens
  • Widest inputsGemini 2.0 FlashGemini 2.0 Flash: Text, Images, PDFs, Audio, Video · o3-pro: Text, Images · Claude Opus 4: Text, Images, PDFs
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGemini 2.0 Flasho3-proClaude Opus 4
CapabilityCapabilities Index (ECI)67%597569
Inputs & features20%907070
Context window13%613232
Overall100%65/10068/10064/100

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 vs Claude Opus 4 specifications side by side
SpecificationGemini 2.0 FlashGoogleo3-proOpenAIClaude Opus 4Anthropic
Capability
Capabilities Index (ECI)134.7147.4 (best)142.7
ECI rank#116 of 148#60 of 148 (best)#87 of 148
GPQA DiamondGraduate-level science questions——76.3%
OTIS Mock AIME 2024–2025Competition mathematics——64.4%
SWE-bench VerifiedFixing real GitHub issues——70.7%
Price per million tokens
Input—$20.00$15.00 (best)
Output—$80.00$75.00 (best)
Cached input———
Blended (3:1)—$35.00$30.00 (best)
Long-context rate—Same rateSame rate
Price source—Official OpenAI APIMedian of 5 providers
Limits
Context window1,048,576 tokens (best)200,000 tokens200,000 tokens
Max output8,192 tokens100,000 tokens (best)32,000 tokens
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesNoYes
AudioYesNoNo
VideoYesNoNo
ReasoningNoYeslow · medium · highYes
Tool callingYesYesYes
Structured outputYesYesNo
Availability
WeightsProprietaryProprietaryProprietary
API model ID—o3-pro—
API providers—6 (best)5
ReleasedDec 11, 2024Jun 10, 2025May 22, 2025
Knowledge cutoffJun 2024May 2024Mar 31, 2025
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
  • Claude Opus 4$300.00
04 — Questions

Which should you choose?

Which is better: Gemini 2.0 Flash, o3-pro or Claude Opus 4?

It is close. Our weighted score puts them within 3 points (o3-pro 68/100, Gemini 2.0 Flash 65/100, Claude Opus 4 64/100), so choose by what matters most for your work: o3-pro for raw capability, Claude Opus 4 on price 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, o3-pro or Claude Opus 4?

Claude Opus 4 is cheaper at $15.00 input / $75.00 output per million tokens (median across 5 API providers). o3-pro costs $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 $30.00 per million tokens for Claude Opus 4 versus $35.00 for o3-pro (1.2× as much). 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), Claude Opus 4 142.7 (#87 of 148) and Gemini 2.0 Flash 134.7 (#116 of 148). Their confidence ranges do not overlap (145.8–149.7 vs 140.2–144.2), 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. All three 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 and 200,000 for Claude Opus 4. Maximum output per response: Gemini 2.0 Flash up to 8,192, o3-pro up to 100,000, Claude Opus 4 up to 32,000 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; Claude Opus 4 accepts text, images and PDFs. Gemini 2.0 Flash handles the widest range of inputs.

Are any of these open source?

No. Gemini 2.0 Flash, o3-pro and Claude Opus 4 are proprietary and only available through APIs and apps.

Which is newer?

o3-pro is the newest, released Jun 10, 2025. Claude Opus 4 came out May 22, 2025; Gemini 2.0 Flash came out Dec 11, 2024. Knowledge cutoff: Gemini 2.0 Flash Jun 2024, o3-pro May 2024, Claude Opus 4 Mar 31, 2025.

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.