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Comparison · 3 models · Updated Oct 4, 2026

o3-pro vs GPT-5.1 vs Claude Opus 4.1

GPT-5.1 comes out ahead, 60 to 51 and 49 on our weighted score, and it is the cheaper option too.

  1. OpenAI

    o3-pro

    Released Jun 10, 2025

    51/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
  2. Our pick

    OpenAI

    GPT-5.1

    Released Nov 13, 2025

    60/100
    • ECI149.7
    • Price$1.25 / $10.00
    • Context400K
  3. Anthropic

    Claude Opus 4.1

    Released Aug 5, 2025

    49/100
    • ECI144.1
    • Price$15.00 / $75.00
    • Context200K
01 — Verdict

GPT-5.1 is our pick

GPT-5.1 is the better all-round choice, scoring 60/100 against o3-pro (51) and Claude Opus 4.1 (49). It leads on capability, price and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGPT-5.1Capabilities Index (ECI): GPT-5.1 149.7 · o3-pro 147.4 · Claude Opus 4.1 144.1
  • Lowest priceGPT-5.1GPT-5.1 $3.44 · Claude Opus 4.1 $30.00 · o3-pro $35.00 per 1M tokens (3:1 blend)
  • Longest contextGPT-5.1GPT-5.1 400,000 · o3-pro 200,000 · Claude Opus 4.1 200,000 tokens
  • Widest inputsClaude Opus 4.1o3-pro: Text, Images · GPT-5.1: Text, Images · Claude Opus 4.1: Text, Images, PDFs
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeighto3-proGPT-5.1Claude Opus 4.1
CapabilityCapabilities Index (ECI)50%757871
Price25%0240
Inputs & features15%707070
Context window10%324432
Overall100%51/10060/10049/100
02 — Side by side

Every spec in one table

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

o3-pro vs GPT-5.1 vs Claude Opus 4.1 specifications side by side
Specificationo3-proOpenAIGPT-5.1OpenAIClaude Opus 4.1Anthropic
Capability
Capabilities Index (ECI)147.4149.7 (best)144.1
ECI rank#60 of 148#52 of 148 (best)#81 of 148
GPQA DiamondGraduate-level science questions—87.6% (best)77.3%
FrontierMath Tiers 1–3Research-level mathematics——12.6%
OTIS Mock AIME 2024–2025Competition mathematics—88.6% (best)68.9%
SWE-bench VerifiedFixing real GitHub issues—68.0%73.4% (best)
SimpleQA VerifiedShort factual questions—48.0%—
Price per million tokens
Input$20.00$1.25 (best)$15.00
Output$80.00$10.00 (best)$75.00
Cached input—$0.125—
Blended (3:1)$35.00$3.44 (best)$30.00
Long-context rateSame rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial OpenAI APIMedian of 14 providers
Limits
Context window200,000 tokens400,000 tokens (best)200,000 tokens
Max output100,000 tokens128,000 tokens (best)32,000 tokens
Inputs and features
TextYesYesYes
ImagesYesYesYes
PDFsNoNoYes
AudioNoNoNo
VideoNoNoNo
ReasoningYeslow · medium · highYeslow · medium · highYes
Tool callingYesYesYes
Structured outputYesYesNo
Availability
WeightsProprietaryProprietaryProprietary
API model IDo3-progpt-5.1—
API providers621 (best)14
ReleasedJun 10, 2025Nov 13, 2025Aug 5, 2025
Knowledge cutoffMay 2024Sep 30, 2024Mar 31, 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.

  • o3-pro$360.00
  • GPT-5.1$32.50
  • Claude Opus 4.1$300.00
04 — Questions

Which should you choose?

Which is better: o3-pro, GPT-5.1 or Claude Opus 4.1?

GPT-5.1 is the better all-round choice, scoring 60/100 against o3-pro (51) and Claude Opus 4.1 (49). It leads on capability, price and context window. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, o3-pro, GPT-5.1 or Claude Opus 4.1?

GPT-5.1 is cheaper at $1.25 input / $10.00 output per million tokens (official OpenAI API price). Claude Opus 4.1 costs $15.00 input / $75.00 output per million tokens (median across 14 API providers); o3-pro costs $20.00 input / $80.00 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 GPT-5.1 versus $30.00 for Claude Opus 4.1 (8.7× as much) and $35.00 for o3-pro (10× as much).

Which scores higher on benchmarks?

GPT-5.1 scores higher on the Capabilities Index (ECI): GPT-5.1 149.7 (#52 of 148), o3-pro 147.4 (#60 of 148) and Claude Opus 4.1 144.1 (#81 of 148). The confidence ranges of the top two overlap (148.3–151.1 vs 145.8–149.7), so treat the gap as small.

Which is better for coding?

There are no published SWE-bench Verified results for o3-pro yet, so there is no like-for-like coding score. On overall capability, GPT-5.1 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?

GPT-5.1 has the largest context window at 400,000 tokens, against 200,000 for o3-pro and 200,000 for Claude Opus 4.1. Maximum output per response: o3-pro up to 100,000, GPT-5.1 up to 128,000, Claude Opus 4.1 up to 32,000 tokens.

Which can read images, PDFs, audio or video?

o3-pro accepts text and images; GPT-5.1 accepts text and images; Claude Opus 4.1 accepts text, images and PDFs. Claude Opus 4.1 handles the widest range of inputs.

Are any of these open source?

No. o3-pro, GPT-5.1 and Claude Opus 4.1 are proprietary and only available through APIs and apps.

Which is newer?

GPT-5.1 is the newest, released Nov 13, 2025. Claude Opus 4.1 came out Aug 5, 2025; o3-pro came out Jun 10, 2025. Knowledge cutoff: o3-pro May 2024, GPT-5.1 Sep 30, 2024, Claude Opus 4.1 Mar 31, 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.