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Llama 3.1 Nemotron Ultra 253B v1 vs LongCat-2.5

LongCat-2.5 leads the LLM Stats Score 50.0 to 18.5.

NVIDIA · Meituan · Updated for 2026

Which is better?

LongCat-2.5 leads the overall LLM Stats Score 50.0 to 18.5, ranking #20 overall.

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

Choose Llama 3.1 Nemotron Ultra 253B v1

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

Choose LongCat-2.5

  • overall performance matters — it scores 50.0 and ranks #20 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you want the most recent training data — it shipped Nov 2026

At a glance

The differences that matter most.

Llama 3.1 Nemotron Ultra 253B v1
NVIDIA
LongCat-2.5
Meituan
Core performance indexes
LLM Stats Score
18.5
#245
50.0
#20
Reasoning
18.3
#242
48.3
#21
Coding
12.4
#175
38.6
#27
Cost, coverage & limits
Benchmark wins
—
—
Input price
— / M
$0.30 / M
Output price
— / M
$1.20 / M
Context window
—
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Llama 3.1 Nemotron Ultra 253B v1
LongCat-2.5
Math
15.6#231
37.2#37
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

6 reported for Llama 3.1 Nemotron Ultra 253B v1 · 23 for LongCat-2.5

No common benchmarks found

Llama 3.1 Nemotron Ultra 253B v1 and LongCat-2.5don'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

Model Size

Parameter count comparison

1347.0B diff

LongCat-2.5 has 1347.0B more parameters than Llama 3.1 Nemotron Ultra 253B v1, making it 532.4% larger.

NVIDIA
Llama 3.1 Nemotron Ultra 253B v1
253.0Bparameters
Meituan
LongCat-2.5
1.6Tparameters
253.0B
Llama 3.1 Nemotron Ultra 253B v1
1600.0B
LongCat-2.5

Context Window

Maximum input and output token capacity

Only LongCat-2.5 specifies input context (1,048,576 tokens). Only LongCat-2.5 specifies output context (131,072 tokens).

NVIDIA
Llama 3.1 Nemotron Ultra 253B v1
Input- tokens
Output- tokens
Meituan
LongCat-2.5
Input1,048,576 tokens
Output131,072 tokens
Sat Nov 07 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

LongCat-2.5 supports multimodal inputs, whereas Llama 3.1 Nemotron Ultra 253B v1 does not.

LongCat-2.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Llama 3.1 Nemotron Ultra 253B v1

Text
Images
Audio
Video

LongCat-2.5

Text
Images
Audio
Video

Release Timeline

When each model was launched

Llama 3.1 Nemotron Ultra 253B v1 was released on 2025-04-07, while LongCat-2.5 was released on 2026-11-01.

LongCat-2.5 is 19 months newer than Llama 3.1 Nemotron Ultra 253B v1.

Llama 3.1 Nemotron Ultra 253B v1

Apr 7, 2025

1.6 years ago

LongCat-2.5

Nov 1, 2026

6 days ago

1.6yr newer

Knowledge Cutoff

When training data ends

Llama 3.1 Nemotron Ultra 253B v1 has a documented knowledge cutoff of 2023-12-01, while LongCat-2.5's cutoff date is not specified.

We can confirm Llama 3.1 Nemotron Ultra 253B v1's training data extends to 2023-12-01, but cannot make a direct comparison without LongCat-2.5's cutoff date.

Llama 3.1 Nemotron Ultra 253B v1

Dec 2023

LongCat-2.5

—

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Llama 3.1 Nemotron Ultra 253B v1 and LongCat-2.5 side-by-side, then vote on the output you prefer.

Llama 3.1 Nemotron Ultra 253B v1
✓ Preferred
LongCat-2.5
Open in Playground

FAQ

Common questions about Llama 3.1 Nemotron Ultra 253B v1 vs LongCat-2.5.

Which is better, Llama 3.1 Nemotron Ultra 253B v1 or LongCat-2.5?

LongCat-2.5 leads the LLM Stats Score 50.0 to 18.5. Llama 3.1 Nemotron Ultra 253B v1 is made by NVIDIA 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 Llama 3.1 Nemotron Ultra 253B v1 compare to LongCat-2.5 in benchmarks?

Llama 3.1 Nemotron Ultra 253B v1 scores MATH-500: 97.0%, IFEval: 89.5%, GPQA: 76.0%, BFCL v2: 74.1%, AIME 2025: 72.5%. LongCat-2.5 scores MathVision: 96.5%, BrowseComp: 91.9%, CharXiv-R: 90.2%, Terminal-Bench 2.1: 88.4%, Video-MME: 85.2%.

What are the context window sizes for Llama 3.1 Nemotron Ultra 253B v1 and LongCat-2.5?

Llama 3.1 Nemotron Ultra 253B v1 supports an unknown number of 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 Llama 3.1 Nemotron Ultra 253B v1 and LongCat-2.5?

Key differences include LLM Stats Score (18.5 vs 50.0), multimodal support (no vs yes), licensing (Llama 3.1 Community License vs Unknown). See the full comparison above for benchmark-by-benchmark results.

Who makes Llama 3.1 Nemotron Ultra 253B v1 and LongCat-2.5?

Llama 3.1 Nemotron Ultra 253B v1 is developed by NVIDIA and LongCat-2.5 is developed by Meituan.

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