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Comparison · 2 models · Updated Oct 4, 2026

Claude Opus 4 vs Claude Opus 4.1

Too close to call on our weighted score (Claude Opus 4.1 49, Claude Opus 4 48). The right pick depends on what you value most.

  1. Anthropic

    Claude Opus 4

    Released May 22, 2025

    48/100
    • ECI142.7
    • Price$15.00 / $75.00
    • Context200K
    Full specs Remove Claude Opus 4

  2. Anthropic

    Claude Opus 4.1

    Released Aug 5, 2025

    49/100
    • ECI144.1
    • Price$15.00 / $75.00
    • Context200K
    Full specs Remove Claude Opus 4.1

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01 — Verdict

Too close to call

It is close. Our weighted score puts them within a point (Claude Opus 4.1 49/100, Claude Opus 4 48/100), so choose by what matters most for your work: Claude Opus 4.1 for raw capability and Claude Opus 4 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • CapabilityClaude Opus 4.1Capabilities Index (ECI): Claude Opus 4.1 144.1 · Claude Opus 4 142.7
  • Lowest priceSame priceClaude Opus 4 $30.00 · Claude Opus 4.1 $30.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameClaude Opus 4 200,000 · Claude Opus 4.1 200,000 tokens
  • Widest inputsSame inputsClaude Opus 4: Text, Images, PDFs · Claude Opus 4.1: Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightClaude Opus 4Claude Opus 4.1
CapabilityCapabilities Index (ECI)50%6971
Price25%00
Inputs & features15%7070
Context window10%3232
Overall100%48/10049/100
02 — Side by side

Every spec in one table

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

Claude Opus 4 vs Claude Opus 4.1 specifications side by side
SpecificationClaude Opus 4AnthropicClaude Opus 4.1Anthropic
Capability
Capabilities Index (ECI)142.7144.1 (best)
ECI rank#87 of 148#81 of 148 (best)
GPQA DiamondGraduate-level science questions76.3%77.3% (best)
FrontierMath Tiers 1–3Research-level mathematics—12.6%
OTIS Mock AIME 2024–2025Competition mathematics64.4%68.9% (best)
SWE-bench VerifiedFixing real GitHub issues70.7%73.4% (best)
Price per million tokens
Input$15.00$15.00
Output$75.00$75.00
Cached input——
Blended (3:1)$30.00$30.00
Long-context rateSame rateSame rate
Price sourceMedian of 5 providersMedian of 14 providers
Limits
Context window200,000 tokens200,000 tokens
Max output32,000 tokens32,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesYes
AudioNoNo
VideoNoNo
ReasoningYesYes
Tool callingYesYes
Structured outputNoNo
Availability
WeightsProprietaryProprietary
API model ID——
API providers514 (best)
ReleasedMay 22, 2025Aug 5, 2025
Knowledge cutoffMar 31, 2025Mar 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.

  • Claude Opus 4$300.00
  • Claude Opus 4.1$300.00
04 — Questions

Which should you choose?

Which is better: Claude Opus 4 or Claude Opus 4.1?

It is close. Our weighted score puts them within a point (Claude Opus 4.1 49/100, Claude Opus 4 48/100), so choose by what matters most for your work: Claude Opus 4.1 for raw capability and Claude Opus 4 on price. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Claude Opus 4 or Claude Opus 4.1?

Claude Opus 4 and Claude Opus 4.1 cost the same: $15.00 input / $75.00 output per million tokens.

Which scores higher on benchmarks?

Claude Opus 4.1 scores higher on the Capabilities Index (ECI): Claude Opus 4.1 144.1 (#81 of 148) and Claude Opus 4 142.7 (#87 of 148). The confidence ranges of the top two overlap (141.6–146.0 vs 140.2–144.2), so treat the gap as small. On individual benchmarks: GPQA Diamond — Claude Opus 4.1 77.3%, Claude Opus 4 76.3%; OTIS Mock AIME 2024–2025 — Claude Opus 4.1 68.9%, Claude Opus 4 64.4%; SWE-bench Verified — Claude Opus 4.1 73.4%, Claude Opus 4 70.7%.

Which is better for coding?

Claude Opus 4.1 resolves more real GitHub issues on SWE-bench Verified: Claude Opus 4.1 73.4% and Claude Opus 4 70.7%. Both support tool calling for agent workflows.

Which has the bigger context window?

Claude Opus 4 and Claude Opus 4.1 share the same 200,000-token context window. Maximum output per response: Claude Opus 4 up to 32,000, Claude Opus 4.1 up to 32,000 tokens.

Which can read images, PDFs, audio or video?

Claude Opus 4 accepts text, images and PDFs; Claude Opus 4.1 accepts text, images and PDFs. They handle the same number of input types.

Are any of these open source?

No. Claude Opus 4 and Claude Opus 4.1 are proprietary and only available through APIs and apps.

Which is newer?

Claude Opus 4.1 is the newest, released Aug 5, 2025. Claude Opus 4 came out May 22, 2025. Knowledge cutoff: Claude Opus 4 Mar 31, 2025, 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.

05 — Keep comparing

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