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Comparison · 3 models · Updated Oct 4, 2026

Gemini 2.5 Pro vs Claude Opus 4 vs o3

Gemini 2.5 Pro comes out ahead, 63 to 58 and 48 on our weighted score, and it is the cheaper option too.

  1. Our pick

    Google

    Gemini 2.5 Pro

    Released Jun 17, 2025

    63/100
    • ECI145.3
    • Price$1.25 / $10.00
    • Context1.05M
    Full specs Remove Gemini 2.5 Pro

  2. Anthropic

    Claude Opus 4

    Released May 22, 2025

    48/100
    • ECI142.7
    • Price$15.00 / $75.00
    • Context200K
    Full specs Remove Claude Opus 4

  3. OpenAI

    o3

    Released Apr 16, 2025

    58/100
    • ECI146.9
    • Price$2.00 / $8.00
    • Context200K
    Full specs Remove o3
01 — Verdict

Gemini 2.5 Pro is our pick

Gemini 2.5 Pro is the better all-round choice, scoring 63/100 against o3 (58) and Claude Opus 4 (48). It leads on inputs & features and context window. o3 wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • Capabilityo3Capabilities Index (ECI): o3 146.9 · Gemini 2.5 Pro 145.3 · Claude Opus 4 142.7
  • Lowest priceGemini 2.5 ProGemini 2.5 Pro $3.44 · o3 $3.50 · Claude Opus 4 $30.00 per 1M tokens (3:1 blend)
  • Longest contextGemini 2.5 ProGemini 2.5 Pro 1,048,576 · Claude Opus 4 200,000 · o3 200,000 tokens
  • Widest inputsGemini 2.5 ProGemini 2.5 Pro: Text, Images, PDFs, Audio, Video · Claude Opus 4: Text, Images, PDFs · o3: Text, Images, PDFs
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGemini 2.5 ProClaude Opus 4o3
CapabilityCapabilities Index (ECI)50%726974
Price25%24024
Inputs & features15%1007080
Context window10%613232
Overall100%63/10048/10058/100
02 — Side by side

Every spec in one table

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

Gemini 2.5 Pro vs Claude Opus 4 vs o3 specifications side by side
SpecificationGemini 2.5 ProGoogleClaude Opus 4Anthropico3OpenAI
Capability
Capabilities Index (ECI)145.3142.7146.9 (best)
ECI rank#78 of 148#87 of 148#63 of 148 (best)
GPQA DiamondGraduate-level science questions85.3% (best)76.3%81.8%
FrontierMath Tiers 1–3Research-level mathematics24.6%—33.3% (best)
OTIS Mock AIME 2024–2025Competition mathematics84.7% (best)64.4%84.4%
SWE-bench VerifiedFixing real GitHub issues57.6%70.7% (best)62.3%
SimpleQA VerifiedShort factual questions——49.4%
Price per million tokens
Input$1.25 (best)$15.00$2.00
Output$10.00$75.00$8.00 (best)
Cached input$0.125 (best)—$0.50
Blended (3:1)$3.44 (best)$30.00$3.50
Long-context rateOver 200K: $2.50 / $15.00Same rateSame rate
Price sourceOfficial Google APIMedian of 5 providersOfficial OpenAI API
Limits
Context window1,048,576 tokens (best)200,000 tokens200,000 tokens
Max output65,536 tokens32,000 tokens100,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesYesYes
AudioYesNoNo
VideoYesNoNo
ReasoningYesYesYeslow · medium · high
Tool callingYesYesYes
Structured outputYesNoYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgemini-2.5-pro—o3
API providers22 (best)518
ReleasedJun 17, 2025May 22, 2025Apr 16, 2025
Knowledge cutoffJan 2025Mar 31, 2025May 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 2.5 Pro$32.50
  • Claude Opus 4$300.00
  • o3$36.00
04 — Questions

Which should you choose?

Which is better: Gemini 2.5 Pro, Claude Opus 4 or o3?

Gemini 2.5 Pro is the better all-round choice, scoring 63/100 against o3 (58) and Claude Opus 4 (48). It leads on inputs & features and context window. o3 wins on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Gemini 2.5 Pro, Claude Opus 4 or o3?

Gemini 2.5 Pro is cheaper at $1.25 input / $10.00 output per million tokens (official Google API price). o3 costs $2.00 input / $8.00 output per million tokens (official OpenAI API price); Claude Opus 4 costs $15.00 input / $75.00 output per million tokens (median across 5 API providers). At a typical mix of three input tokens to one output token, that is $3.44 per million tokens for Gemini 2.5 Pro versus $3.50 for o3 (1× as much) and $30.00 for Claude Opus 4 (8.7× as much).

Which scores higher on benchmarks?

o3 scores higher on the Capabilities Index (ECI): o3 146.9 (#63 of 148), Gemini 2.5 Pro 145.3 (#78 of 148) and Claude Opus 4 142.7 (#87 of 148). The confidence ranges of the top two overlap (144.9–148.6 vs 143.6–146.9), so treat the gap as small. On individual benchmarks: GPQA Diamond — Gemini 2.5 Pro 85.3%, o3 81.8%, Claude Opus 4 76.3%; OTIS Mock AIME 2024–2025 — Gemini 2.5 Pro 84.7%, o3 84.4%, Claude Opus 4 64.4%; SWE-bench Verified — Claude Opus 4 70.7%, o3 62.3%, Gemini 2.5 Pro 57.6%.

Which is better for coding?

Claude Opus 4 resolves more real GitHub issues on SWE-bench Verified: Claude Opus 4 70.7%, o3 62.3% and Gemini 2.5 Pro 57.6%. All three support tool calling for agent workflows.

Which has the bigger context window?

Gemini 2.5 Pro has the largest context window at 1,048,576 tokens, against 200,000 for Claude Opus 4 and 200,000 for o3. Maximum output per response: Gemini 2.5 Pro up to 65,536, Claude Opus 4 up to 32,000, o3 up to 100,000 tokens.

Which can read images, PDFs, audio or video?

Gemini 2.5 Pro accepts text, images, PDFs, audio and video; Claude Opus 4 accepts text, images and PDFs; o3 accepts text, images and PDFs. Gemini 2.5 Pro handles the widest range of inputs.

Are any of these open source?

No. Gemini 2.5 Pro, Claude Opus 4 and o3 are proprietary and only available through APIs and apps.

Which is newer?

Gemini 2.5 Pro is the newest, released Jun 17, 2025. Claude Opus 4 came out May 22, 2025; o3 came out Apr 16, 2025. Knowledge cutoff: Gemini 2.5 Pro Jan 2025, Claude Opus 4 Mar 31, 2025, o3 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

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