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Claude Opus 5.5 vs Nova 2 Omni

Claude Opus 5.5 leads the LLM Stats Score 59.7 to 25.7.

Anthropic · Amazon · Updated for 2026

Which is better?

Claude Opus 5.5 leads the overall LLM Stats Score 59.7 to 25.7, ranking #1 overall.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Opus 5.5

  • overall performance matters — it scores 59.7 and ranks #1 on LLM Stats
  • your work emphasizes reasoning and agents — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

Choose Nova 2 Omni

  • you are already invested in the Amazon ecosystem

At a glance

The differences that matter most.

Claude Opus 5.5
Anthropic
Nova 2 Omni
Amazon
Core performance indexes
LLM Stats Score
59.7
#1
25.7
#161
Reasoning
57.8
#1
28.0
#137
Agents
44.5
#2
4.6
#157
Cost, coverage & limits
Benchmark wins
—
—
Input price
$4.00 / M
— / M
Output price
$20.00 / M
— / M
Context window
1,000,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Claude Opus 5.5
Nova 2 Omni
Math
42.5#5
25.1#115
Vision
42.8#1
7.2#148
Tool use
32.9#2
14.8#96
Multimodal
42.5#1
8.7#127
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

31 reported for Claude Opus 5.5 · 18 for Nova 2 Omni

No common benchmarks found

Claude Opus 5.5 and Nova 2 Omnidon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Claude Opus 5.5 specifies input context (1,000,000 tokens). Only Claude Opus 5.5 specifies output context (128,000 tokens).

Anthropic
Claude Opus 5.5
Input1,000,000 tokens
Output128,000 tokens
Amazon
Nova 2 Omni
Input- tokens
Output- tokens
Wed Sep 23 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Opus 5.5 and Nova 2 Omni support multimodal inputs.

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

Claude Opus 5.5

Text
Images
Audio
Video

Nova 2 Omni

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 5.5

Proprietary

Closed source

Nova 2 Omni

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 5.5 was released on 2026-09-22, while Nova 2 Omni was released on 2025-12-02.

Claude Opus 5.5 is 10 months newer than Nova 2 Omni.

Claude Opus 5.5

Sep 22, 2026

0 days ago

9mo newer
Nova 2 Omni

Dec 2, 2025

9 months ago

Knowledge Cutoff

When training data ends

Claude Opus 5.5 has a documented knowledge cutoff of 2026-06-01, while Nova 2 Omni's cutoff date is not specified.

We can confirm Claude Opus 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without Nova 2 Omni's cutoff date.

Claude Opus 5.5

Jun 2026

Nova 2 Omni

—

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Opus 5.5 and Nova 2 Omni side-by-side, then vote on the output you prefer.

Claude Opus 5.5
✓ Preferred
Nova 2 Omni
Open in Playground

FAQ

Common questions about Claude Opus 5.5 vs Nova 2 Omni.

Which is better, Claude Opus 5.5 or Nova 2 Omni?

Claude Opus 5.5 leads the LLM Stats Score 59.7 to 25.7. Claude Opus 5.5 is made by Anthropic and Nova 2 Omni is made by Amazon. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Opus 5.5 compare to Nova 2 Omni in benchmarks?

Claude Opus 5.5 scores BenchCAD (with Python tool): 96.2%, Global-MMLU: 94.3%, SWE-bench Multilingual: 93.9%, MILU: 93.1%, ArXivMath: 91.2%. Nova 2 Omni scores AIME 2025: 92.1%, RefCOCOg: 86.3%, ScreenSpot: 85.4%, MMLU-Pro: 80.7%, Tau2 Telecom: 80.0%.

What are the context window sizes for Claude Opus 5.5 and Nova 2 Omni?

Claude Opus 5.5 supports 1.0M tokens and Nova 2 Omni supports an unknown number of 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 5.5 and Nova 2 Omni?

Key differences include LLM Stats Score (59.7 vs 25.7). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 5.5 and Nova 2 Omni?

Claude Opus 5.5 is developed by Anthropic and Nova 2 Omni is developed by Amazon.

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