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Claude Opus 5.5 vs Gemini 4 Argon

Claude Opus 5.5 and Gemini 4 Argon are closely matched at 60.4 and 55.1 on the LLM Stats Score.

Anthropic · Google · Updated for 2026

Which is better?

Claude Opus 5.5 and Gemini 4 Argon are closely matched on the overall LLM Stats Score at 60.4 and 55.1.

In the 6 individual benchmarks reported for both models, Claude Opus 5.5 wins 4; this is a narrower head-to-head signal than the composite indexes.

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

Choose Claude Opus 5.5

  • you value its reported benchmark strengths — it wins 4 of 6 exact shared results

Choose Gemini 4 Argon

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

At a glance

The differences that matter most.

Claude Opus 5.5
Anthropic
Gemini 4 Argon
Google
Core performance indexes
LLM Stats Score
60.4
#1
55.1
#4
Reasoning
59.0
#1
52.4
#7
Coding
51.0
#1
44.1
#4
Agents
45.3
#1
40.5
#4
Cost, coverage & limits
Benchmark wins
4 of 6
2 of 6
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

3 shared
Index
Claude Opus 5.5
Gemini 4 Argon
Vision
41.3#1
36.8#8
Tool use
32.8#3
30.6#6
Multimodal
40.9#1
36.9#8
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

31 reported for Claude Opus 5.5 · 19 for Gemini 4 Argon

6 shared

Claude Opus 5.5 outperforms in 4 benchmarks (FrontierSWE V2, OSWorld 2.0, Terminal-Bench 4.0, Terminal-Bench-Science 0.1), while Gemini 4 Argon is better at 2 benchmarks (AutomationBench, DeepSWE 1.1).

Claude Opus 5.5 shows notably better performance in the majority of benchmarks.

Thu Oct 08 2026 • llm-stats.com

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
Google
Gemini 4 Argon
Input- tokens
Output- tokens
Thu Oct 08 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Opus 5.5 and Gemini 4 Argon 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

Gemini 4 Argon

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

Gemini 4 Argon

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 5.5 was released on 2026-09-22, while Gemini 4 Argon was released on 2026-09-30.

Gemini 4 Argon is 0 month newer than Claude Opus 5.5.

Claude Opus 5.5

Sep 22, 2026

2 weeks ago

Gemini 4 Argon

Sep 30, 2026

1 weeks ago

1w newer

Knowledge Cutoff

When training data ends

Claude Opus 5.5 has a documented knowledge cutoff of 2026-06-01, while Gemini 4 Argon'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 Gemini 4 Argon's cutoff date.

Claude Opus 5.5

Jun 2026

Gemini 4 Argon

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Opus 5.5 and Gemini 4 Argon side-by-side, then vote on the output you prefer.

Claude Opus 5.5
✓ Preferred
Gemini 4 Argon
Open in Playground

FAQ

Common questions about Claude Opus 5.5 vs Gemini 4 Argon.

Which is better, Claude Opus 5.5 or Gemini 4 Argon?

Claude Opus 5.5 and Gemini 4 Argon are closely matched on the LLM Stats Score at 60.4 and 55.1. Claude Opus 5.5 is made by Anthropic and Gemini 4 Argon is made by Google. 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 Gemini 4 Argon 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%. Gemini 4 Argon scores Graphwalks BFS <128k: 99.7%, Vibe Code Bench: 91.9%, LVBench: 91.7%, LABBench2: 88.8%, Graphwalks BFS >128k: 84.2%.

What are the context window sizes for Claude Opus 5.5 and Gemini 4 Argon?

Claude Opus 5.5 supports 1.0M tokens and Gemini 4 Argon 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 Gemini 4 Argon?

Key differences include LLM Stats Score (60.4 vs 55.1). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 5.5 and Gemini 4 Argon?

Claude Opus 5.5 is developed by Anthropic and Gemini 4 Argon is developed by Google.

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