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Claude Opus 5.5 vs LFM2.5-2.6B

Claude Opus 5.5 leads the LLM Stats Score 60.4 to 18.4.

Anthropic · Liquid AI · Updated for 2026

Which is better?

Claude Opus 5.5 leads the overall LLM Stats Score 60.4 to 18.4, 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 60.4 and ranks #1 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

Choose LFM2.5-2.6B

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Opus 5.5
Anthropic
LFM2.5-2.6B
Liquid AI
Core performance indexes
LLM Stats Score
60.4
#1
18.4
#234
Reasoning
59.5
#1
14.1
#255
Coding
49.9
#1
16.0
#148
Agents
45.5
#1
6.7
#162
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

1 shared
Index
Claude Opus 5.5
LFM2.5-2.6B
Tool use
34.3#3
0.3#197
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

31 reported for Claude Opus 5.5 · 9 for LFM2.5-2.6B

No common benchmarks found

Claude Opus 5.5 and LFM2.5-2.6Bdon'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
Liquid AI
LFM2.5-2.6B
Input- tokens
Output- tokens
Fri Oct 23 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Opus 5.5 supports multimodal inputs, whereas LFM2.5-2.6B does not.

Claude Opus 5.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 5.5

Text
Images
Audio
Video

LFM2.5-2.6B

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 5.5 is licensed under a proprietary license, while LFM2.5-2.6B uses LFM Open License v1.0.

License differences may affect how you can use these models in commercial or open-source projects.

Claude Opus 5.5

Proprietary

Closed source

LFM2.5-2.6B

LFM Open License v1.0

Open weights

Release Timeline

When each model was launched

Claude Opus 5.5 was released on 2026-09-22, while LFM2.5-2.6B was released on 2026-08-04.

Claude Opus 5.5 is 2 months newer than LFM2.5-2.6B.

Claude Opus 5.5

Sep 22, 2026

4 weeks ago

1mo newer
LFM2.5-2.6B

Aug 4, 2026

2 months ago

Knowledge Cutoff

When training data ends

Claude Opus 5.5 has a documented knowledge cutoff of 2026-06-01, while LFM2.5-2.6B'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 LFM2.5-2.6B's cutoff date.

Claude Opus 5.5

Jun 2026

LFM2.5-2.6B

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Opus 5.5 and LFM2.5-2.6B side-by-side, then vote on the output you prefer.

Claude Opus 5.5
✓ Preferred
LFM2.5-2.6B
Open in Playground

FAQ

Common questions about Claude Opus 5.5 vs LFM2.5-2.6B.

Which is better, Claude Opus 5.5 or LFM2.5-2.6B?

Claude Opus 5.5 leads the LLM Stats Score 60.4 to 18.4. Claude Opus 5.5 is made by Anthropic and LFM2.5-2.6B is made by Liquid AI. 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 LFM2.5-2.6B 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%. LFM2.5-2.6B scores Multi-IF: 80.1%, PinchBench: 68.2%, Claw-Eval: 62.8%, LiveCodeBench v6: 59.4%, IFBench: 59.2%.

What are the context window sizes for Claude Opus 5.5 and LFM2.5-2.6B?

Claude Opus 5.5 supports 1.0M tokens and LFM2.5-2.6B 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 LFM2.5-2.6B?

Key differences include LLM Stats Score (60.4 vs 18.4), multimodal support (yes vs no), licensing (Proprietary vs LFM Open License v1.0). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 5.5 and LFM2.5-2.6B?

Claude Opus 5.5 is developed by Anthropic and LFM2.5-2.6B is developed by Liquid AI.

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