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Grok-4 Heavy vs LongCat-Flash-Thinking

Grok-4 Heavy leads the LLM Stats Score 40.7 to 28.6.

xAI · Meituan · Updated for 2026

Which is better?

Grok-4 Heavy leads the overall LLM Stats Score 40.7 to 28.6, ranking #54 overall.

In the 3 individual benchmarks reported for both models, Grok-4 Heavy wins 2; 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 Grok-4 Heavy

  • overall performance matters — it scores 40.7 and ranks #54 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 2 of 3 exact shared results

Choose LongCat-Flash-Thinking

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

At a glance

The differences that matter most.

Core performance indexes
40.7
#54
28.6
#132
39.0
#57
28.8
#123
17.7
#114
14.0
#134
Cost, coverage & limits
Benchmark wins
2 of 3
1 of 3
Input price
— / M
$0.30 / M
Output price
— / M
$1.20 / M
Context window
128,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Grok-4 Heavy
LongCat-Flash-Thinking
41.5#6
28.1#95
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

6 reported for Grok-4 Heavy · 14 for LongCat-Flash-Thinking

3 shared

Grok-4 Heavy outperforms in 2 benchmarks (AIME 2025, GPQA), while LongCat-Flash-Thinking is better at 0 benchmarks.

Grok-4 Heavy shows notably better performance in the majority of benchmarks.

Sun Sep 13 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only LongCat-Flash-Thinking specifies input context (128,000 tokens). Only LongCat-Flash-Thinking specifies output context (128,000 tokens).

xAI
Grok-4 Heavy
Input- tokens
Output- tokens
Meituan
LongCat-Flash-Thinking
Input128,000 tokens
Output128,000 tokens
Sun Sep 13 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Grok-4 Heavy supports multimodal inputs, whereas LongCat-Flash-Thinking does not.

Grok-4 Heavy can handle both text and other forms of data like images, making it suitable for multimodal applications.

Grok-4 Heavy

Text
Images
Audio
Video

LongCat-Flash-Thinking

Text
Images
Audio
Video

License

Usage and distribution terms

Grok-4 Heavy is licensed under a proprietary license, while LongCat-Flash-Thinking uses MIT.

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

Grok-4 Heavy

Proprietary

Closed source

LongCat-Flash-Thinking

MIT

Open weights

Release Timeline

When each model was launched

LongCat-Flash-Thinking was released on 2025-09-22, while Grok-4 Heavy's release date is not specified.

We can confirm LongCat-Flash-Thinking's release timeline, but cannot make a direct age comparison without Grok-4 Heavy's release date.

Grok-4 Heavy

LongCat-Flash-Thinking

Sep 22, 2025

11 months ago

Knowledge Cutoff

When training data ends

Grok-4 Heavy has a documented knowledge cutoff of 2024-12-31, while LongCat-Flash-Thinking's cutoff date is not specified.

We can confirm Grok-4 Heavy's training data extends to 2024-12-31, but cannot make a direct comparison without LongCat-Flash-Thinking's cutoff date.

Grok-4 Heavy

Dec 2024

LongCat-Flash-Thinking

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Grok-4 Heavy and LongCat-Flash-Thinking side-by-side, then vote on the output you prefer.

Grok-4 Heavy
✓ Preferred
LongCat-Flash-Thinking
Open in Playground

FAQ

Common questions about Grok-4 Heavy vs LongCat-Flash-Thinking.

Which is better, Grok-4 Heavy or LongCat-Flash-Thinking?

Grok-4 Heavy leads the LLM Stats Score 40.7 to 28.6. Grok-4 Heavy is made by xAI and LongCat-Flash-Thinking is made by Meituan. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Grok-4 Heavy compare to LongCat-Flash-Thinking in benchmarks?

Grok-4 Heavy scores AIME 2025: 100.0%, HMMT25: 96.7%, GPQA: 88.4%, LiveCodeBench: 79.4%, USAMO25: 61.9%. LongCat-Flash-Thinking scores MATH-500: 99.2%, ZebraLogic: 95.5%, AIME 2024: 93.3%, AIME 2025: 90.6%, MMLU-Redux: 89.3%.

What are the context window sizes for Grok-4 Heavy and LongCat-Flash-Thinking?

Grok-4 Heavy supports an unknown number of tokens and LongCat-Flash-Thinking supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Grok-4 Heavy and LongCat-Flash-Thinking?

Key differences include LLM Stats Score (40.7 vs 28.6), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Grok-4 Heavy and LongCat-Flash-Thinking?

Grok-4 Heavy is developed by xAI and LongCat-Flash-Thinking is developed by Meituan.