Model Comparison

Claude Opus 4.5 vs o3-proWhich is better in 2026?

Comparing Claude Opus 4.5 and o3-pro across benchmarks, pricing, and capabilities.

Verdict: Claude Opus 4.5 vs o3-pro — which is better?

Claude Opus 4.5 (by Anthropic) and o3-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.

On price, Claude Opus 4.5 is roughly 3.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Claude Opus 4.5 if…

  • cost matters — it's about 3.5x cheaper per token
  • you want the most recent training data — it shipped Nov 2025

Choose o3-pro if…

  • you want predictable pricing at $20.00/M input and $80.00/M output
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Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Claude Opus 4.5 and o3-prodon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Claude Opus 4.5 costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 4.0x cheaper than o3-pro ($20.00/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 3.2x cheaper than o3-pro ($80.00/1M tokens).

In conclusion, o3-pro is more expensive than Claude Opus 4.5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Sat Jun 13 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
OpenAI
o3-pro
Input tokens$20.00
Output tokens$80.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Both models have the same input context window of 200,000 tokens. o3-pro can generate longer responses up to 100,000 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
OpenAI
o3-pro
Input200,000 tokens
Output100,000 tokens
Sat Jun 13 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 4.5 and o3-pro support multimodal inputs.

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

Claude Opus 4.5

Text
Images
Audio
Video

o3-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 4.5

Proprietary

Closed source

o3-pro

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while o3-pro was released on 2025-06-10.

Claude Opus 4.5 is 6 months newer than o3-pro.

Claude Opus 4.5

Nov 24, 2025

6 months ago

5mo newer
o3-pro

Jun 10, 2025

1.0 years ago

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a knowledge cutoff of 2025-03-31, while o3-pro has a cutoff of 2024-05-31.

Claude Opus 4.5 has more recent training data (up to 2025-03-31), making it potentially better informed about events through that date compared to o3-pro (2024-05-31).

Claude Opus 4.5

Mar 2025

10 mo newer
o3-pro

May 2024

Provider Availability

Claude Opus 4.5 is available from Anthropic. o3-pro is available from OpenAI.

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

o3-pro

openai logo
OpenAI
Input Price:Input: $20.00/1MOutput Price:Output: $80.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Less expensive input tokens
Less expensive output tokens
OpenAI

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

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Opus 4.5
OpenAI
o3-pro

FAQ

Common questions about Claude Opus 4.5 vs o3-pro.

Which is better, Claude Opus 4.5 or o3-pro?

Claude Opus 4.5 (Anthropic) and o3-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 4.5 compare to o3-pro in benchmarks?

Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%.

Is Claude Opus 4.5 cheaper than o3-pro?

Claude Opus 4.5 is 4.0x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. o3-pro costs $20.00/M input and $80.00/M output via openai.

What are the context window sizes for Claude Opus 4.5 and o3-pro?

Claude Opus 4.5 supports 200K tokens and o3-pro supports 200K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 4.5 and o3-pro?

Key differences include input pricing ($5.00 vs $20.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and o3-pro?

Claude Opus 4.5 is developed by Anthropic and o3-pro is developed by OpenAI.

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