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Comparison · 2 models · Updated Oct 4, 2026

Claude Opus 4 vs o3-pro

o3-pro comes out ahead, 51 to 48 on our weighted score, though Claude Opus 4 is 14% cheaper per token.

  1. Anthropic

    Claude Opus 4

    Released May 22, 2025

    48/100
    • ECI142.7
    • Price$15.00 / $75.00
    • Context200K
  2. Our pick

    OpenAI

    o3-pro

    Released Jun 10, 2025

    51/100
    • ECI147.4
    • Price$20.00 / $80.00
    • Context200K
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01 — Verdict

o3-pro is our pick

o3-pro is the better all-round choice, scoring 51/100 against Claude Opus 4 (48). It leads on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

  • Capabilityo3-proCapabilities Index (ECI): o3-pro 147.4 · Claude Opus 4 142.7
  • Lowest priceClaude Opus 4Claude Opus 4 $30.00 · o3-pro $35.00 per 1M tokens (3:1 blend)
  • Longest contextAbout the sameClaude Opus 4 200,000 · o3-pro 200,000 tokens
  • Widest inputsClaude Opus 4Claude Opus 4: Text, Images, PDFs · o3-pro: Text, Images
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightClaude Opus 4o3-pro
CapabilityCapabilities Index (ECI)50%6975
Price25%00
Inputs & features15%7070
Context window10%3232
Overall100%48/10051/100
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 o3-pro specifications side by side
SpecificationClaude Opus 4Anthropico3-proOpenAI
Capability
Capabilities Index (ECI)142.7147.4 (best)
ECI rank#87 of 148#60 of 148 (best)
GPQA DiamondGraduate-level science questions76.3%—
OTIS Mock AIME 2024–2025Competition mathematics64.4%—
SWE-bench VerifiedFixing real GitHub issues70.7%—
Price per million tokens
Input$15.00 (best)$20.00
Output$75.00 (best)$80.00
Cached input——
Blended (3:1)$30.00 (best)$35.00
Long-context rateSame rateSame rate
Price sourceMedian of 5 providersOfficial OpenAI API
Limits
Context window200,000 tokens200,000 tokens
Max output32,000 tokens100,000 tokens (best)
Inputs and features
TextYesYes
ImagesYesYes
PDFsYesNo
AudioNoNo
VideoNoNo
ReasoningYesYeslow · medium · high
Tool callingYesYes
Structured outputNoYes
Availability
WeightsProprietaryProprietary
API model ID—o3-pro
API providers56 (best)
ReleasedMay 22, 2025Jun 10, 2025
Knowledge cutoffMar 31, 2025May 2024
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
  • o3-pro$360.00
04 — Questions

Which should you choose?

Which is better: Claude Opus 4 or o3-pro?

o3-pro is the better all-round choice, scoring 51/100 against Claude Opus 4 (48). It leads on capability. The score weighs capability 50%, price 25%, inputs & features 15%, context window 10%.

Which is cheaper, Claude Opus 4 or o3-pro?

Claude Opus 4 is cheaper at $15.00 input / $75.00 output per million tokens (median across 5 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 $30.00 per million tokens for Claude Opus 4 versus $35.00 for o3-pro (1.2× as much).

Which scores higher on benchmarks?

o3-pro scores higher on the Capabilities Index (ECI): o3-pro 147.4 (#60 of 148) and Claude Opus 4 142.7 (#87 of 148). Their confidence ranges do not overlap (145.8–149.7 vs 140.2–144.2), so the gap is a real one.

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, o3-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?

Claude Opus 4 and o3-pro share the same 200,000-token context window. Maximum output per response: Claude Opus 4 up to 32,000, o3-pro up to 100,000 tokens.

Which can read images, PDFs, audio or video?

Claude Opus 4 accepts text, images and PDFs; o3-pro accepts text and images. Claude Opus 4 handles the widest range of inputs.

Are any of these open source?

No. Claude Opus 4 and o3-pro are proprietary and only available through APIs and apps.

Which is newer?

o3-pro is the newest, released Jun 10, 2025. Claude Opus 4 came out May 22, 2025. Knowledge cutoff: Claude Opus 4 Mar 31, 2025, o3-pro May 2024.

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.