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Comparison · 3 models · Updated Oct 4, 2026

Gemini 3.1 Pro Preview vs GPT-5.1 vs Claude Opus 4.5

Gemini 3.1 Pro Preview comes out ahead, 68 to 60 and 55 on our weighted score, though GPT-5.1 is 24% cheaper per token.

  1. Our pick

    Google

    Gemini 3.1 Pro Preview

    Released Feb 19, 2026

    68/100
    • ECI154.8
    • Price$2.00 / $12.00
    • Context1.05M
    Full specs Remove Gemini 3.1 Pro Preview

  2. OpenAI

    GPT-5.1

    Released Nov 13, 2025

    60/100
    • ECI149.7
    • Price$1.25 / $10.00
    • Context400K
    Full specs Remove GPT-5.1

  3. Anthropic

    Claude Opus 4.5

    Released Nov 24, 2025

    55/100
    • ECI150.1
    • Price$5.00 / $25.00
    • Context200K
    Full specs Remove Claude Opus 4.5
01 — Verdict

Gemini 3.1 Pro Preview is our pick

Gemini 3.1 Pro Preview is the better all-round choice, scoring 68/100 against GPT-5.1 (60) and Claude Opus 4.5 (55). It leads on capability, inputs & features and context window. GPT-5.1 wins on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGemini 3.1 Pro PreviewCapabilities Index (ECI): Gemini 3.1 Pro Preview 154.8 · Claude Opus 4.5 150.1 · GPT-5.1 149.7
  • Lowest priceGPT-5.1GPT-5.1 $3.44 · Gemini 3.1 Pro Preview $4.50 · Claude Opus 4.5 $10.00 per 1M tokens (3:1 blend)
  • Longest contextGemini 3.1 Pro PreviewGemini 3.1 Pro Preview 1,048,576 · GPT-5.1 400,000 · Claude Opus 4.5 200,000 tokens
  • Widest inputsGemini 3.1 Pro PreviewGemini 3.1 Pro Preview: Text, Images, PDFs, Audio, Video · GPT-5.1: Text, Images · Claude Opus 4.5: Text, Images, PDFs
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightGemini 3.1 Pro PreviewGPT-5.1Claude Opus 4.5
CapabilityCapabilities Index (ECI)50%847878
Price25%19242
Inputs & features15%1007080
Context window10%614432
Overall100%68/10060/10055/100
02 — Side by side

Every spec in one table

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

Gemini 3.1 Pro Preview vs GPT-5.1 vs Claude Opus 4.5 specifications side by side
SpecificationGemini 3.1 Pro PreviewGoogleGPT-5.1OpenAIClaude Opus 4.5Anthropic
Capability
Capabilities Index (ECI)154.8 (best)149.7150.1
ECI rank#31 of 148 (best)#52 of 148#48 of 148
GPQA DiamondGraduate-level science questions94.4% (best)87.6%86.1%
FrontierMath Tiers 1–3Research-level mathematics59.7% (best)—34.4%
OTIS Mock AIME 2024–2025Competition mathematics95.6% (best)88.6%86.1%
SWE-bench VerifiedFixing real GitHub issues75.6%68.0%76.7% (best)
SimpleQA VerifiedShort factual questions73.5% (best)48.0%45.7%
Price per million tokens
Input$2.00$1.25 (best)$5.00
Output$12.00$10.00 (best)$25.00
Cached input$0.20$0.125 (best)$0.50
Blended (3:1)$4.50$3.44 (best)$10.00
Long-context rateOver 200K: $4.00 / $18.00Same rateSame rate
Price sourceOfficial Google APIOfficial OpenAI APIOfficial Anthropic API
Limits
Context window1,048,576 tokens (best)400,000 tokens200,000 tokens
Max output65,536 tokens128,000 tokens (best)64,000 tokens
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsYesNoYes
AudioYesNoNo
VideoYesNoNo
ReasoningYeslow · medium · highYeslow · medium · highYeslow · medium · high
Tool callingYesYesYes
Structured outputYesYesYes
Availability
WeightsProprietaryProprietaryProprietary
API model IDgemini-3.1-pro-previewgpt-5.1claude-opus-4-5
API providers262128 (best)
ReleasedFeb 19, 2026Nov 13, 2025Nov 24, 2025
Knowledge cutoffJan 2025Sep 30, 2024May 2025
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 3.1 Pro Preview$44.00
  • GPT-5.1$32.50
  • Claude Opus 4.5$100.00
04 — Questions

Which should you choose?

Which is better: Gemini 3.1 Pro Preview, GPT-5.1 or Claude Opus 4.5?

Gemini 3.1 Pro Preview is the better all-round choice, scoring 68/100 against GPT-5.1 (60) and Claude Opus 4.5 (55). It leads on capability, inputs & features and context window. GPT-5.1 wins on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Gemini 3.1 Pro Preview, GPT-5.1 or Claude Opus 4.5?

GPT-5.1 is cheaper at $1.25 input / $10.00 output per million tokens (official OpenAI API price). Gemini 3.1 Pro Preview costs $2.00 input / $12.00 output per million tokens (official Google API price); Claude Opus 4.5 costs $5.00 input / $25.00 output per million tokens (official Anthropic API price). At a typical mix of three input tokens to one output token, that is $3.44 per million tokens for GPT-5.1 versus $4.50 for Gemini 3.1 Pro Preview (1.3× as much) and $10.00 for Claude Opus 4.5 (2.9× as much).

Which scores higher on benchmarks?

Gemini 3.1 Pro Preview scores higher on the Capabilities Index (ECI): Gemini 3.1 Pro Preview 154.8 (#31 of 148), Claude Opus 4.5 150.1 (#48 of 148) and GPT-5.1 149.7 (#52 of 148). The confidence ranges of the top two overlap (152.6–157.3 vs 147.9–153.0), so treat the gap as small. On individual benchmarks: GPQA Diamond — Gemini 3.1 Pro Preview 94.4%, GPT-5.1 87.6%, Claude Opus 4.5 86.1%; OTIS Mock AIME 2024–2025 — Gemini 3.1 Pro Preview 95.6%, GPT-5.1 88.6%, Claude Opus 4.5 86.1%; SWE-bench Verified — Claude Opus 4.5 76.7%, Gemini 3.1 Pro Preview 75.6%, GPT-5.1 68.0%; SimpleQA Verified — Gemini 3.1 Pro Preview 73.5%, GPT-5.1 48.0%, Claude Opus 4.5 45.7%.

Which is better for coding?

Claude Opus 4.5 resolves more real GitHub issues on SWE-bench Verified: Claude Opus 4.5 76.7%, Gemini 3.1 Pro Preview 75.6% and GPT-5.1 68.0%. All three support tool calling for agent workflows.

Which has the bigger context window?

Gemini 3.1 Pro Preview has the largest context window at 1,048,576 tokens, against 400,000 for GPT-5.1 and 200,000 for Claude Opus 4.5. Maximum output per response: Gemini 3.1 Pro Preview up to 65,536, GPT-5.1 up to 128,000, Claude Opus 4.5 up to 64,000 tokens.

Which can read images, PDFs, audio or video?

Gemini 3.1 Pro Preview accepts text, images, PDFs, audio and video; GPT-5.1 accepts text and images; Claude Opus 4.5 accepts text, images and PDFs. Gemini 3.1 Pro Preview handles the widest range of inputs.

Are any of these open source?

No. Gemini 3.1 Pro Preview, GPT-5.1 and Claude Opus 4.5 are proprietary and only available through APIs and apps.

Which is newer?

Gemini 3.1 Pro Preview is the newest, released Feb 19, 2026. Claude Opus 4.5 came out Nov 24, 2025; GPT-5.1 came out Nov 13, 2025. Knowledge cutoff: Gemini 3.1 Pro Preview Jan 2025, GPT-5.1 Sep 30, 2024, Claude Opus 4.5 May 2025.

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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