ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Gemini 2.5 Pro vs Claude Sonnet 4 vs o3

Gemini 2.5 Pro comes out ahead, 63 to 58 and 51 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
  2. Anthropic

    Claude Sonnet 4

    Released May 22, 2025

    51/100
    • ECI141.7
    • Price$3.00 / $15.00
    • Context200K
  3. OpenAI

    o3

    Released Apr 16, 2025

    58/100
    • ECI146.9
    • Price$2.00 / $8.00
    • Context200K
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 Sonnet 4 (51). 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 Sonnet 4 141.7
  • Lowest priceGemini 2.5 ProGemini 2.5 Pro $3.44 · o3 $3.50 · Claude Sonnet 4 $6.00 per 1M tokens (3:1 blend)
  • Longest contextGemini 2.5 ProGemini 2.5 Pro 1,048,576 · Claude Sonnet 4 200,000 · o3 200,000 tokens
  • Widest inputsGemini 2.5 ProGemini 2.5 Pro: Text, Images, PDFs, Audio, Video · Claude Sonnet 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 Sonnet 4o3
CapabilityCapabilities Index (ECI)50%726874
Price25%241324
Inputs & features15%1007080
Context window10%613232
Overall100%63/10051/10058/100
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 Sonnet 4 vs o3 specifications side by side
SpecificationGemini 2.5 ProGoogleClaude Sonnet 4Anthropico3OpenAI
Capability
Capabilities Index (ECI)145.3141.7146.9 (best)
ECI rank#78 of 148#94 of 148#63 of 148 (best)
GPQA DiamondGraduate-level science questions85.3% (best)79.2%81.8%
FrontierMath Tiers 1–3Research-level mathematics24.6%—33.3% (best)
OTIS Mock AIME 2024–2025Competition mathematics84.7% (best)71.1%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)$3.00$2.00
Output$10.00$15.00$8.00 (best)
Cached input$0.125 (best)—$0.50
Blended (3:1)$3.44 (best)$6.00$3.50
Long-context rateOver 200K: $2.50 / $15.00Same rateSame rate
Price sourceOfficial Google APIMedian of 9 providersOfficial OpenAI API
Limits
Context window1,048,576 tokens (best)200,000 tokens200,000 tokens
Max output65,536 tokens64,000 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)918
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 Sonnet 4$60.00
  • o3$36.00
04 — Questions

Which should you choose?

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

Gemini 2.5 Pro is the better all-round choice, scoring 63/100 against o3 (58) and Claude Sonnet 4 (51). 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 Sonnet 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 Sonnet 4 costs $3.00 input / $15.00 output per million tokens (median across 9 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 $6.00 for Claude Sonnet 4 (1.7× 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 Sonnet 4 141.7 (#94 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 Sonnet 4 79.2%; OTIS Mock AIME 2024–2025 — Gemini 2.5 Pro 84.7%, o3 84.4%, Claude Sonnet 4 71.1%.

Which is better for coding?

There are no published SWE-bench Verified results for Claude Sonnet 4 yet, so there is no like-for-like coding score. On overall capability, o3 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 2.5 Pro has the largest context window at 1,048,576 tokens, against 200,000 for Claude Sonnet 4 and 200,000 for o3. Maximum output per response: Gemini 2.5 Pro up to 65,536, Claude Sonnet 4 up to 64,000, 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 Sonnet 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 Sonnet 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 Sonnet 4 came out May 22, 2025; o3 came out Apr 16, 2025. Knowledge cutoff: Gemini 2.5 Pro Jan 2025, Claude Sonnet 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.