Model Comparison

Claude Opus 4.5 vs o1Which is better in 2026?

Claude Opus 4.5 significantly outperforms across most benchmarks. Claude Opus 4.5 is 2.6x cheaper per token.

Verdict: Claude Opus 4.5 vs o1 — which is better?

Claude Opus 4.5 (by Anthropic) and o1 (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.

Claude Opus 4.5 outperforms in 3 benchmarks (GPQA, MMMLU, SWE-Bench Verified), while o1 is better at 0 benchmarks. Claude Opus 4.5 significantly outperforms across most benchmarks.

On price, Claude Opus 4.5 is roughly 2.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Choose Claude Opus 4.5 if…

  • you want the strongest raw capability — it leads on 3 of 3 shared benchmarks
  • cost matters — it's about 2.6x cheaper per token
  • you want the most recent training data — it shipped Nov 2025

Choose o1 if…

  • you want predictable pricing at $15.00/M input and $60.00/M output
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Performance Benchmarks

Comparative analysis across standard metrics

3 benchmarks

Claude Opus 4.5 outperforms in 3 benchmarks (GPQA, MMMLU, SWE-Bench Verified), while o1 is better at 0 benchmarks.

Claude Opus 4.5 significantly outperforms across most benchmarks.

Sat Jun 06 2026 • llm-stats.com

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 3.0x cheaper than o1 ($15.00/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 2.4x cheaper than o1 ($60.00/1M tokens).

In conclusion, o1 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 06 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
OpenAI
o1
Input tokens$15.00
Output tokens$60.00
Best providerAzure
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. o1 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
o1
Input200,000 tokens
Output100,000 tokens
Sat Jun 06 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude Opus 4.5 supports multimodal inputs, whereas o1 does not.

Claude Opus 4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 4.5

Text
Images
Audio
Video

o1

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

o1

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while o1 was released on 2024-12-17.

Claude Opus 4.5 is 11 months newer than o1.

Claude Opus 4.5

Nov 24, 2025

6 months ago

11mo newer
o1

Dec 17, 2024

1.5 years ago

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a documented knowledge cutoff of 2025-03-31, while o1's cutoff date is not specified.

We can confirm Claude Opus 4.5's training data extends to 2025-03-31, but cannot make a direct comparison without o1's cutoff date.

Claude Opus 4.5

Mar 2025

o1

—

Provider Availability

Claude Opus 4.5 is available from Anthropic. o1 is available from Azure, OpenAI.

Claude Opus 4.5

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

o1

azure logo
Azure
Input Price:Input: $15.00/1MOutput Price:Output: $60.00/1M
openai logo
OpenAI
Input Price:Input: $15.00/1MOutput Price:Output: $60.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Anthropic
Supports multimodal inputs
Less expensive input tokens
Less expensive output tokens
Higher GPQA score (87.0% vs 78.0%)
Higher MMMLU score (90.8% vs 87.7%)
Higher SWE-Bench Verified score (80.9% vs 41.0%)
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
o1

FAQ

Common questions about Claude Opus 4.5 vs o1.

Which is better, Claude Opus 4.5 or o1?

Claude Opus 4.5 significantly outperforms across most benchmarks. Claude Opus 4.5 is made by Anthropic and o1 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Opus 4.5 compare to o1 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%. o1 scores GSM8k: 97.1%, MATH: 96.4%, GPQA Physics: 92.8%, MMLU: 91.8%, MGSM: 89.3%.

Is Claude Opus 4.5 cheaper than o1?

Claude Opus 4.5 is 3.0x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. o1 costs $15.00/M input and $60.00/M output via azure.

What are the context window sizes for Claude Opus 4.5 and o1?

Claude Opus 4.5 supports 200K tokens and o1 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 o1?

Key differences include input pricing ($5.00 vs $15.00/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and o1?

Claude Opus 4.5 is developed by Anthropic and o1 is developed by OpenAI.

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