Model Comparison

Claude Opus 5 vs o1-proWhich is better in 2026?

Comparing Claude Opus 5 and o1-pro across benchmarks, pricing, and capabilities.

Verdict: Claude Opus 5 vs o1-pro — which is better?

Claude Opus 5 (by Anthropic) and o1-pro (by OpenAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Choose Claude Opus 5 if…

  • you want the most recent training data — it shipped Jul 2026

Choose o1-pro if…

  • you are already invested in the OpenAI ecosystem

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Claude Opus 5 and o1-prodon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only Claude Opus 5 specifies input context (1,000,000 tokens). Only Claude Opus 5 specifies output context (128,000 tokens).

Anthropic
Claude Opus 5
Input1,000,000 tokens
Output128,000 tokens
OpenAI
o1-pro
Input- tokens
Output- tokens
Sat Jul 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 5 and o1-pro support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Opus 5

Text
Images
Audio
Video

o1-pro

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Opus 5

Proprietary

Closed source

o1-pro

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 5 was released on 2026-07-24, while o1-pro was released on 2024-12-17.

Claude Opus 5 is 19 months newer than o1-pro.

Claude Opus 5

Jul 24, 2026

0 days ago

1.6yr newer
o1-pro

Dec 17, 2024

1.6 years ago

Knowledge Cutoff

When training data ends

o1-pro has a documented knowledge cutoff of 2023-09-30, while Claude Opus 5's cutoff date is not specified.

We can confirm o1-pro's training data extends to 2023-09-30, but cannot make a direct comparison without Claude Opus 5's cutoff date.

Claude Opus 5

—

o1-pro

Sep 2023

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (1,000,000 tokens)
OpenAI

No standout differentiators in the data we have for this pair.

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Opus 5 and o1-pro side-by-side, then vote on the output you prefer.

Claude Opus 5
✓ Preferred
o1-pro
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Opus 5
OpenAI
o1-pro

FAQ

Common questions about Claude Opus 5 vs o1-pro.

Which is better, Claude Opus 5 or o1-pro?

Claude Opus 5 (Anthropic) and o1-pro (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Claude Opus 5 compare to o1-pro in benchmarks?

Claude Opus 5 scores BrowseComp: 90.8%, BioMysteryBench: 90.1%, OSWorld 2.0: 70.6%, DeepSWE 1.1: 68.8%, Humanity's Last Exam: 64.7%. o1-pro scores AIME 2024: 86.0%, GPQA: 79.0%.

What are the context window sizes for Claude Opus 5 and o1-pro?

Claude Opus 5 supports 1.0M tokens and o1-pro supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

Who makes Claude Opus 5 and o1-pro?

Claude Opus 5 is developed by Anthropic and o1-pro is developed by OpenAI.

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