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Comparison · 2 models · Updated Oct 4, 2026

Gemini 2.5 Pro vs o3

Gemini 2.5 Pro comes out ahead, 63 to 58 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. OpenAI

    o3

    Released Apr 16, 2025

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

  3. Add a model

    Make it a three-way comparison.

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). 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
  • Lowest priceGemini 2.5 ProGemini 2.5 Pro $3.44 · o3 $3.50 per 1M tokens (3:1 blend)
  • Longest contextGemini 2.5 ProGemini 2.5 Pro 1,048,576 · o3 200,000 tokens
  • Widest inputsGemini 2.5 ProGemini 2.5 Pro: Text, Images, PDFs, Audio, Video · o3: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGemini 2.5 Proo3
CapabilityCapabilities Index (ECI)50%7274
Price25%2424
Inputs & features15%10080
Context window10%6132
Overall100%63/10058/100
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 o3 specifications side by side
SpecificationGemini 2.5 ProGoogleo3OpenAI
Capability
Capabilities Index (ECI)145.3146.9 (best)
ECI rank#78 of 148#63 of 148 (best)
GPQA DiamondGraduate-level science questions85.3% (best)81.8%
FrontierMath Tiers 1–3Research-level mathematics24.6%33.3% (best)
OTIS Mock AIME 2024–2025Competition mathematics84.7% (best)84.4%
SWE-bench VerifiedFixing real GitHub issues57.6%62.3% (best)
SimpleQA VerifiedShort factual questions—49.4%
Price per million tokens
Input$1.25 (best)$2.00
Output$10.00$8.00 (best)
Cached input$0.125 (best)$0.50
Blended (3:1)$3.44 (best)$3.50
Long-context rateOver 200K: $2.50 / $15.00Same rate
Price sourceOfficial Google APIOfficial OpenAI API
Limits
Context window1,048,576 tokens (best)200,000 tokens
Max output65,536 tokens100,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesYes
AudioYesNo
VideoYesNo
ReasoningYesYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgemini-2.5-proo3
API providers22 (best)18
ReleasedJun 17, 2025Apr 16, 2025
Knowledge cutoffJan 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
  • o3$36.00
04 — Questions

Which should you choose?

Which is better: Gemini 2.5 Pro or o3?

Gemini 2.5 Pro is the better all-round choice, scoring 63/100 against o3 (58). 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 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). 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).

Which scores higher on benchmarks?

o3 scores higher on the Capabilities Index (ECI): o3 146.9 (#63 of 148) and Gemini 2.5 Pro 145.3 (#78 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%; FrontierMath Tiers 1–3 — o3 33.3%, Gemini 2.5 Pro 24.6%; OTIS Mock AIME 2024–2025 — Gemini 2.5 Pro 84.7%, o3 84.4%; SWE-bench Verified — o3 62.3%, Gemini 2.5 Pro 57.6%.

Which is better for coding?

o3 resolves more real GitHub issues on SWE-bench Verified: o3 62.3% and Gemini 2.5 Pro 57.6%. Both 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 o3. Maximum output per response: Gemini 2.5 Pro up to 65,536, 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; 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 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. o3 came out Apr 16, 2025. Knowledge cutoff: Gemini 2.5 Pro Jan 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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