Model Comparison

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

Claude Opus 4.5 significantly outperforms across most benchmarks. o3-mini is 5.2x cheaper per token.

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

Claude Opus 4.5 (by Anthropic) and o3-mini (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 2 benchmarks (GPQA, SWE-Bench Verified), while o3-mini is better at 0 benchmarks. Claude Opus 4.5 significantly outperforms across most benchmarks.

On price, o3-mini is roughly 5.2x 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 2 of 2 shared benchmarks
  • you want the most recent training data — it shipped Nov 2025

Choose o3-mini if…

  • cost matters — it's about 5.2x cheaper per token
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Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Claude Opus 4.5 outperforms in 2 benchmarks (GPQA, SWE-Bench Verified), while o3-mini 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

o3-mini costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 4.5x more expensive than o3-mini ($1.10/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 5.7x more expensive than o3-mini ($4.40/1M tokens).

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

* 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
o3-mini
Input tokens$1.10
Output tokens$4.40
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. o3-mini 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-mini
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 o3-mini 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

o3-mini

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-mini

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while o3-mini was released on 2025-01-30.

Claude Opus 4.5 is 10 months newer than o3-mini.

Claude Opus 4.5

Nov 24, 2025

6 months ago

9mo newer
o3-mini

Jan 30, 2025

1.3 years ago

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a knowledge cutoff of 2025-03-31, while o3-mini has a cutoff of 2023-09-30.

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-mini (2023-09-30).

Claude Opus 4.5

Mar 2025

1.5 yr newer
o3-mini

Sep 2023

Provider Availability

Claude Opus 4.5 is available from Anthropic. o3-mini is available from Azure, OpenAI.

Claude Opus 4.5

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

o3-mini

azure logo
Azure
Input Price:Input: $1.10/1MOutput Price:Output: $4.40/1M
openai logo
OpenAI
Input Price:Input: $1.10/1MOutput Price:Output: $4.40/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Anthropic
Supports multimodal inputs
Higher GPQA score (87.0% vs 77.2%)
Higher SWE-Bench Verified score (80.9% vs 49.3%)
OpenAI
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

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

FAQ

Common questions about Claude Opus 4.5 vs o3-mini.

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

Claude Opus 4.5 significantly outperforms across most benchmarks. Claude Opus 4.5 is made by Anthropic and o3-mini 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 o3-mini 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%. o3-mini scores COLLIE: 98.7%, MATH: 97.9%, IFEval: 93.9%, MGSM: 92.0%, AIME 2024: 87.3%.

Is Claude Opus 4.5 cheaper than o3-mini?

o3-mini is 4.5x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. o3-mini costs $1.10/M input and $4.40/M output via azure.

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

Claude Opus 4.5 supports 200K tokens and o3-mini 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-mini?

Key differences include input pricing ($5.00 vs $1.10/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and o3-mini?

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

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