ZMIME
Comparison · 3 models · Updated Oct 4, 2026

Gemini 3 Pro Preview vs GPT-5.2 vs Claude Sonnet 5.5

Claude Sonnet 5.5 comes out ahead, 72 to 67 and 61 on our weighted score, and it is the cheaper option too.

  1. Google

    Gemini 3 Pro Preview

    Released Nov 18, 2025

    67/100
    • ECI153.0
    • Price$2.00 / $12.00
    • Context1.05M
  2. OpenAI

    GPT-5.2

    Released Dec 11, 2025

    61/100
    • ECI153.5
    • Price$1.75 / $14.00
    • Context400K
  3. Our pick

    Anthropic

    Claude Sonnet 5.5

    Released Sep 28, 2026

    72/100
    • ECI165.2
    • Price$2.00 / $10.00
    • Context1M
01 — Verdict

Claude Sonnet 5.5 is our pick

Claude Sonnet 5.5 is the better all-round choice, scoring 72/100 against Gemini 3 Pro Preview (67) and GPT-5.2 (61). It leads on capability and price. Gemini 3 Pro Preview wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityClaude Sonnet 5.5Capabilities Index (ECI): Claude Sonnet 5.5 165.2 · GPT-5.2 153.5 · Gemini 3 Pro Preview 153.0
  • Lowest priceClaude Sonnet 5.5Claude Sonnet 5.5 $4.00 · Gemini 3 Pro Preview $4.50 · GPT-5.2 $4.81 per 1M tokens (3:1 blend)
  • Longest contextGemini 3 Pro PreviewGemini 3 Pro Preview 1,048,576 · Claude Sonnet 5.5 1,000,000 · GPT-5.2 400,000 tokens
  • Widest inputsGemini 3 Pro PreviewGemini 3 Pro Preview: Text, Images, PDFs, Audio, Video · GPT-5.2: Text, Images · Claude Sonnet 5.5: Text, Images, PDFs
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGemini 3 Pro PreviewGPT-5.2Claude Sonnet 5.5
CapabilityCapabilities Index (ECI)50%828397
Price25%191821
Inputs & features15%1007080
Context window10%614460
Overall100%67/10061/10072/100
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 GPT-5.2 vs Claude Sonnet 5.5 specifications side by side
SpecificationGemini 3 Pro PreviewGoogleGPT-5.2OpenAIClaude Sonnet 5.5Anthropic
Capability
Capabilities Index (ECI)153.0153.5165.2 (best)
ECI rank#39 of 148#38 of 148#3 of 148 (best)
GPQA DiamondGraduate-level science questions92.6%91.4%95.6% (best)
FrontierMath Tiers 1–3Research-level mathematics—67.4%88.8% (best)
OTIS Mock AIME 2024–2025Competition mathematics91.4%96.1%100% (best)
SWE-bench VerifiedFixing real GitHub issues72.9%73.8% (best)—
SimpleQA VerifiedShort factual questions—37.1%46.5% (best)
Price per million tokens
Input$2.00$1.75 (best)$2.00
Output$12.00$14.00$10.00 (best)
Cached input—$0.175 (best)$0.20
Blended (3:1)$4.50$4.81$4.00 (best)
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 2 providersOfficial OpenAI APIOfficial Anthropic API
Limits
Context window1,048,576 tokens (best)400,000 tokens1,000,000 tokens
Max output65,536 tokens128,000 tokens (best)128,000 tokens (best)
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesNoYes
AudioYesNoNo
VideoYesNoNo
ReasoningYesYeslow · medium · high · xhighYeslow · medium · high · xhigh · max
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model ID—gpt-5.2claude-sonnet-5-5
API providers32123 (best)
ReleasedNov 18, 2025Dec 11, 2025Sep 28, 2026
Knowledge cutoffJan 2025Aug 31, 2025Jun 2026
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
  • GPT-5.2$45.50
  • Claude Sonnet 5.5$40.00
04 — Questions

Which should you choose?

Which is better: Gemini 3 Pro Preview, GPT-5.2 or Claude Sonnet 5.5?

Claude Sonnet 5.5 is the better all-round choice, scoring 72/100 against Gemini 3 Pro Preview (67) and GPT-5.2 (61). It leads on capability and price. Gemini 3 Pro Preview wins on inputs & features. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Gemini 3 Pro Preview, GPT-5.2 or Claude Sonnet 5.5?

Claude Sonnet 5.5 is cheaper at $2.00 input / $10.00 output per million tokens (official Anthropic API price). Gemini 3 Pro Preview costs $2.00 input / $12.00 output per million tokens (median across 2 API providers); GPT-5.2 costs $1.75 input / $14.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $4.00 per million tokens for Claude Sonnet 5.5 versus $4.50 for Gemini 3 Pro Preview (1.1× as much) and $4.81 for GPT-5.2 (1.2× as much).

Which scores higher on benchmarks?

Claude Sonnet 5.5 scores higher on the Capabilities Index (ECI): Claude Sonnet 5.5 165.2 (#3 of 148), GPT-5.2 153.5 (#38 of 148) and Gemini 3 Pro Preview 153.0 (#39 of 148). Their confidence ranges do not overlap (161.8–169.4 vs 151.7–155.4), so the gap is a real one. On individual benchmarks: GPQA Diamond — Claude Sonnet 5.5 95.6%, Gemini 3 Pro Preview 92.6%, GPT-5.2 91.4%; OTIS Mock AIME 2024–2025 — Claude Sonnet 5.5 100%, GPT-5.2 96.1%, Gemini 3 Pro Preview 91.4%.

Which is better for coding?

There are no published SWE-bench Verified results for Claude Sonnet 5.5 yet, so there is no like-for-like coding score. On overall capability, Claude Sonnet 5.5 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 3 Pro Preview has the largest context window at 1,048,576 tokens, against 1,000,000 for Claude Sonnet 5.5 and 400,000 for GPT-5.2. Maximum output per response: Gemini 3 Pro Preview up to 65,536, GPT-5.2 up to 128,000, Claude Sonnet 5.5 up to 128,000 tokens.

Which can read images, PDFs, audio or video?

Gemini 3 Pro Preview accepts text, images, PDFs, audio and video; GPT-5.2 accepts text and images; Claude Sonnet 5.5 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, GPT-5.2 and Claude Sonnet 5.5 are proprietary and only available through APIs and apps.

Which is newer?

Claude Sonnet 5.5 is the newest, released Sep 28, 2026. GPT-5.2 came out Dec 11, 2025; Gemini 3 Pro Preview came out Nov 18, 2025. Knowledge cutoff: Gemini 3 Pro Preview Jan 2025, GPT-5.2 Aug 31, 2025, Claude Sonnet 5.5 Jun 2026.

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.