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Comparison · 2 models · Updated Oct 4, 2026

GPT-5 Pro vs Claude Opus 4.5

Too close to call on our weighted score (Claude Opus 4.5 55, GPT-5 Pro 54). The right pick depends on what you value most.

  1. OpenAI

    GPT-5 Pro

    Released Oct 6, 2025

    54/100
    • ECI150.3
    • Price$15.00 / $120.00
    • Context400K
    Full specs Remove GPT-5 Pro

  2. 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

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01 — Verdict

Too close to call

It is close. Our weighted score puts them within a point (Claude Opus 4.5 55/100, GPT-5 Pro 54/100), so choose by what matters most for your work: GPT-5 Pro for raw capability and Claude Opus 4.5 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityGPT-5 ProCapabilities Index (ECI): GPT-5 Pro 150.3 · Claude Opus 4.5 150.1
  • Lowest priceClaude Opus 4.5Claude Opus 4.5 $10.00 · GPT-5 Pro $41.25 per 1M tokens (3:1 blend)
  • Longest contextGPT-5 ProGPT-5 Pro 400,000 · Claude Opus 4.5 200,000 tokens
  • Widest inputsClaude Opus 4.5GPT-5 Pro: Text, Images · Claude Opus 4.5: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5 ProClaude Opus 4.5
CapabilityCapabilities Index (ECI)50%7878
Price25%02
Inputs & features15%7080
Context window10%4432
Overall100%54/10055/100
02 — Side by side

Every spec in one table

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

GPT-5 Pro vs Claude Opus 4.5 specifications side by side
SpecificationGPT-5 ProOpenAIClaude Opus 4.5Anthropic
Capability
Capabilities Index (ECI)150.3 (best)150.1
ECI rank#46 of 148 (best)#48 of 148
GPQA DiamondGraduate-level science questions—86.1%
FrontierMath Tiers 1–3Research-level mathematics55.8% (best)34.4%
OTIS Mock AIME 2024–2025Competition mathematics—86.1%
SWE-bench VerifiedFixing real GitHub issues—76.7%
SimpleQA VerifiedShort factual questions—45.7%
Price per million tokens
Input$15.00$5.00 (best)
Output$120.00$25.00 (best)
Cached input—$0.50
Blended (3:1)$41.25$10.00 (best)
Long-context rateSame rateSame rate
Price sourceOfficial OpenAI APIOfficial Anthropic API
Limits
Context window400,000 tokens (best)200,000 tokens
Max output272,000 tokens (best)64,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoNoNo
ReasoningYeshighYeslow · medium · high
Tool callingYesYes
Structured outputYesYes
Availability
WeightsProprietaryProprietary
API model IDgpt-5-proclaude-opus-4-5
API providers1228 (best)
ReleasedOct 6, 2025Nov 24, 2025
Knowledge cutoffSep 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.

  • GPT-5 Pro$390.00
  • Claude Opus 4.5$100.00
04 — Questions

Which should you choose?

Which is better: GPT-5 Pro or Claude Opus 4.5?

It is close. Our weighted score puts them within a point (Claude Opus 4.5 55/100, GPT-5 Pro 54/100), so choose by what matters most for your work: GPT-5 Pro for raw capability and Claude Opus 4.5 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, GPT-5 Pro or Claude Opus 4.5?

Claude Opus 4.5 is cheaper at $5.00 input / $25.00 output per million tokens (official Anthropic API price). GPT-5 Pro costs $15.00 input / $120.00 output per million tokens (official OpenAI API price). At a typical mix of three input tokens to one output token, that is $10.00 per million tokens for Claude Opus 4.5 versus $41.25 for GPT-5 Pro (4.1× as much).

Which scores higher on benchmarks?

GPT-5 Pro scores higher on the Capabilities Index (ECI): GPT-5 Pro 150.3 (#46 of 148) and Claude Opus 4.5 150.1 (#48 of 148). The confidence ranges of the top two overlap (148.5–152.8 vs 147.9–153.0), so treat the gap as small. On individual benchmarks: FrontierMath Tiers 1–3 — GPT-5 Pro 55.8%, Claude Opus 4.5 34.4%.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5 Pro yet, so there is no like-for-like coding score. On overall capability, GPT-5 Pro leads, which tends to carry over to coding, but test on your own codebase. Both support tool calling for agent workflows.

Which has the bigger context window?

GPT-5 Pro has the largest context window at 400,000 tokens, against 200,000 for Claude Opus 4.5. Maximum output per response: GPT-5 Pro up to 272,000, Claude Opus 4.5 up to 64,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5 Pro accepts text and images; Claude Opus 4.5 accepts text, images and PDFs. Claude Opus 4.5 handles the widest range of inputs.

Are any of these open source?

No. GPT-5 Pro and Claude Opus 4.5 are proprietary and only available through APIs and apps.

Which is newer?

Claude Opus 4.5 is the newest, released Nov 24, 2025. GPT-5 Pro came out Oct 6, 2025. Knowledge cutoff: GPT-5 Pro 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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