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Comparison · 2 models · Updated Oct 4, 2026

Gemini 3 Pro Preview vs o3

Gemini 3 Pro Preview comes out ahead, 67 to 58 on our weighted score, though o3 is 22% cheaper per token.

  1. Our pick

    Google

    Gemini 3 Pro Preview

    Released Nov 18, 2025

    67/100
    • ECI153.0
    • Price$2.00 / $12.00
    • Context1.05M
    Full specs Remove Gemini 3 Pro Preview

  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 3 Pro Preview is our pick

Gemini 3 Pro Preview is the better all-round choice, scoring 67/100 against o3 (58). It leads on capability, inputs & features and context window. o3 wins on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGemini 3 Pro PreviewCapabilities Index (ECI): Gemini 3 Pro Preview 153.0 · o3 146.9
  • Lowest priceo3o3 $3.50 · Gemini 3 Pro Preview $4.50 per 1M tokens (3:1 blend)
  • Longest contextGemini 3 Pro PreviewGemini 3 Pro Preview 1,048,576 · o3 200,000 tokens
  • Widest inputsGemini 3 Pro PreviewGemini 3 Pro Preview: Text, Images, PDFs, Audio, Video · o3: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGemini 3 Pro Previewo3
CapabilityCapabilities Index (ECI)50%8274
Price25%1924
Inputs & features15%10080
Context window10%6132
Overall100%67/10058/100
02 — Side by side

Every spec in one table

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

Gemini 3 Pro Preview vs o3 specifications side by side
SpecificationGemini 3 Pro PreviewGoogleo3OpenAI
Capability
Capabilities Index (ECI)153.0 (best)146.9
ECI rank#39 of 148 (best)#63 of 148
GPQA DiamondGraduate-level science questions92.6% (best)81.8%
FrontierMath Tiers 1–3Research-level mathematics—33.3%
OTIS Mock AIME 2024–2025Competition mathematics91.4% (best)84.4%
SWE-bench VerifiedFixing real GitHub issues72.9% (best)62.3%
SimpleQA VerifiedShort factual questions—49.4%
Price per million tokens
Input$2.00$2.00
Output$12.00$8.00 (best)
Cached input—$0.50
Blended (3:1)$4.50$3.50 (best)
Long-context rateSame rateSame rate
Price sourceMedian of 2 providersOfficial 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 ID—o3
API providers318 (best)
ReleasedNov 18, 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 3 Pro Preview$44.00
  • o3$36.00
04 — Questions

Which should you choose?

Which is better: Gemini 3 Pro Preview or o3?

Gemini 3 Pro Preview is the better all-round choice, scoring 67/100 against o3 (58). It leads on capability, inputs & features and context window. o3 wins on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Gemini 3 Pro Preview or o3?

o3 is cheaper at $2.00 input / $8.00 output per million tokens (official OpenAI API price). Gemini 3 Pro Preview costs $2.00 input / $12.00 output per million tokens (median across 2 API providers). At a typical mix of three input tokens to one output token, that is $3.50 per million tokens for o3 versus $4.50 for Gemini 3 Pro Preview (1.3× as much).

Which scores higher on benchmarks?

Gemini 3 Pro Preview scores higher on the Capabilities Index (ECI): Gemini 3 Pro Preview 153.0 (#39 of 148) and o3 146.9 (#63 of 148). Their confidence ranges do not overlap (150.6–155.2 vs 144.9–148.6), so the gap is a real one. On individual benchmarks: GPQA Diamond — Gemini 3 Pro Preview 92.6%, o3 81.8%; OTIS Mock AIME 2024–2025 — Gemini 3 Pro Preview 91.4%, o3 84.4%; SWE-bench Verified — Gemini 3 Pro Preview 72.9%, o3 62.3%.

Which is better for coding?

Gemini 3 Pro Preview resolves more real GitHub issues on SWE-bench Verified: Gemini 3 Pro Preview 72.9% and o3 62.3%. Both support tool calling for agent workflows.

Which has the bigger context window?

Gemini 3 Pro Preview has the largest context window at 1,048,576 tokens, against 200,000 for o3. Maximum output per response: Gemini 3 Pro Preview up to 65,536, o3 up to 100,000 tokens.

Which can read images, PDFs, audio or video?

Gemini 3 Pro Preview accepts text, images, PDFs, audio and video; o3 accepts text, images and PDFs. Gemini 3 Pro Preview handles the widest range of inputs.

Are any of these open source?

No. Gemini 3 Pro Preview and o3 are proprietary and only available through APIs and apps.

Which is newer?

Gemini 3 Pro Preview is the newest, released Nov 18, 2025. o3 came out Apr 16, 2025. Knowledge cutoff: Gemini 3 Pro Preview 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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