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Claude Sonnet 5.5 vs LongCat-2.5

Claude Sonnet 5.5 leads the LLM Stats Score 57.9 to 50.0. LongCat-2.5 is 7.6x cheaper per token.

Anthropic · Meituan · Updated for 2026

Which is better?

Claude Sonnet 5.5 leads the overall LLM Stats Score 57.9 to 50.0, ranking #3 overall.

In the 3 individual benchmarks reported for both models, Claude Sonnet 5.5 wins 3; this is a narrower head-to-head signal than the composite indexes.

On price, LongCat-2.5 is roughly 7.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

LongCat-2.5 also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

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

Choose Claude Sonnet 5.5

  • overall performance matters — it scores 57.9 and ranks #3 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 3 of 3 exact shared results

Choose LongCat-2.5

  • cost matters — it's about 7.6x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Nov 2026

At a glance

The differences that matter most.

Claude Sonnet 5.5
Anthropic
LongCat-2.5
Meituan
Core performance indexes
LLM Stats Score
57.9
#3
50.0
#20
Reasoning
56.0
#2
48.3
#21
Coding
48.7
#2
38.6
#27
Agents
43.5
#4
36.3
#23
Cost, coverage & limits
Benchmark wins
3 of 3
0 of 3
Input price
$2.00 / M
$0.30 / M
Output price
$10.00 / M
$1.20 / M
Context window
1,000,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
Claude Sonnet 5.5
LongCat-2.5
Math
38.1#28
37.2#37
Vision
39.8#6
32.5#29
Tool use
35.9#2
30.2#15
Multimodal
40.0#3
34.8#15
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

47 reported for Claude Sonnet 5.5 · 23 for LongCat-2.5

3 shared

Claude Sonnet 5.5 outperforms in 3 benchmarks (DeepSWE 1.1, Program Bench, Terminal-Bench 4.0), while LongCat-2.5 is better at 0 benchmarks.

Claude Sonnet 5.5 significantly outperforms across most benchmarks.

Fri Nov 06 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

LongCat-2.5 costs less

For input processing, Claude Sonnet 5.5 ($2.00/1M tokens) is 6.7x more expensive than LongCat-2.5 ($0.30/1M tokens).

For output processing, Claude Sonnet 5.5 ($10.00/1M tokens) is 8.3x more expensive than LongCat-2.5 ($1.20/1M tokens).

In conclusion, Claude Sonnet 5.5 is more expensive than LongCat-2.5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Nov 06 2026 • llm-stats.com
Anthropic
Claude Sonnet 5.5
Input tokens$2.00
Output tokens$10.00
Best providerAnthropic
Meituan
LongCat-2.5
Input tokens$0.30
Output tokens$1.20
Best providerMeituan
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

LongCat-2.5 accepts 1,048,576 input tokens compared to Claude Sonnet 5.5's 1,000,000 tokens. LongCat-2.5 can generate longer responses up to 131,072 tokens, while Claude Sonnet 5.5 is limited to 128,000 tokens.

Anthropic
Claude Sonnet 5.5
Input1,000,000 tokens
Output128,000 tokens
Meituan
LongCat-2.5
Input1,048,576 tokens
Output131,072 tokens
Fri Nov 06 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Sonnet 5.5 and LongCat-2.5 support multimodal inputs.

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

Claude Sonnet 5.5

Text
Images
Audio
Video

LongCat-2.5

Text
Images
Audio
Video

Release Timeline

When each model was launched

Claude Sonnet 5.5 was released on 2026-09-28, while LongCat-2.5 was released on 2026-11-01.

LongCat-2.5 is 1 month newer than Claude Sonnet 5.5.

Claude Sonnet 5.5

Sep 28, 2026

1 months ago

LongCat-2.5

Nov 1, 2026

4 days ago

1mo newer

Knowledge Cutoff

When training data ends

Claude Sonnet 5.5 has a documented knowledge cutoff of 2026-06-01, while LongCat-2.5's cutoff date is not specified.

We can confirm Claude Sonnet 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without LongCat-2.5's cutoff date.

Claude Sonnet 5.5

Jun 2026

LongCat-2.5

—

Provider Availability

Claude Sonnet 5.5 is available from Anthropic. LongCat-2.5 is available from Meituan.

Claude Sonnet 5.5

anthropic logo
Anthropic
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M

LongCat-2.5

meituan logo
Meituan
Input Price:Input: $0.30/1MOutput Price:Output: $1.20/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Sonnet 5.5 and LongCat-2.5 side-by-side, then vote on the output you prefer.

Claude Sonnet 5.5
✓ Preferred
LongCat-2.5
Open in Playground

FAQ

Common questions about Claude Sonnet 5.5 vs LongCat-2.5.

Which is better, Claude Sonnet 5.5 or LongCat-2.5?

Claude Sonnet 5.5 leads the LLM Stats Score 57.9 to 50.0. Claude Sonnet 5.5 is made by Anthropic and LongCat-2.5 is made by Meituan. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Sonnet 5.5 compare to LongCat-2.5 in benchmarks?

Claude Sonnet 5.5 scores BenchCAD (with Python tool): 96.3%, ArXivMath (with tools): 95.2%, Global-MMLU: 92.1%, MILU: 91.6%, SWE-bench Multilingual: 90.3%. LongCat-2.5 scores MathVision: 96.5%, BrowseComp: 91.9%, CharXiv-R: 90.2%, Terminal-Bench 2.1: 88.4%, Video-MME: 85.2%.

Is Claude Sonnet 5.5 cheaper than LongCat-2.5?

LongCat-2.5 is 6.7x cheaper for input tokens. Claude Sonnet 5.5 costs $2.00/M input and $10.00/M output via anthropic. LongCat-2.5 costs $0.30/M input and $1.20/M output via meituan.

What are the context window sizes for Claude Sonnet 5.5 and LongCat-2.5?

Claude Sonnet 5.5 supports 1.0M tokens and LongCat-2.5 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Sonnet 5.5 and LongCat-2.5?

Key differences include LLM Stats Score (57.9 vs 50.0), context window (1.0M vs 1.0M), input pricing ($2.00 vs $0.30/M), licensing (Proprietary vs Unknown). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 5.5 and LongCat-2.5?

Claude Sonnet 5.5 is developed by Anthropic and LongCat-2.5 is developed by Meituan.

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