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Kimi K2 0905 vs Llama 3.1 Nemotron Ultra 253B v1

Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1 are closely matched at 21.6 and 19.1 on the LLM Stats Score.

Moonshot AI · NVIDIA · Updated for 2026

Which is better?

Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1 are closely matched on the overall LLM Stats Score at 21.6 and 19.1.

In the 1 individual benchmarks reported for both models, Llama 3.1 Nemotron Ultra 253B v1 wins 1; 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 Kimi K2 0905

  • you want the most recent training data — it shipped Sep 2025

Choose Llama 3.1 Nemotron Ultra 253B v1

  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Kimi K2 0905
Moonshot AI
Llama 3.1 Nemotron Ultra 253B v1
NVIDIA
Core performance indexes
LLM Stats Score
21.6
#185
19.1
#206
Reasoning
22.0
#173
18.8
#205
Coding
19.4
#104
12.4
#146
Cost, coverage & limits
Benchmark wins
0 of 1
1 of 1
Input price
$0.60 / M
— / M
Output price
$2.50 / M
— / M
Context window
262,144
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Kimi K2 0905
Llama 3.1 Nemotron Ultra 253B v1
Math
24.3#117
15.6#214
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

6 reported for Kimi K2 0905 · 6 for Llama 3.1 Nemotron Ultra 253B v1

1 shared

Kimi K2 0905 outperforms in 0 benchmarks, while Llama 3.1 Nemotron Ultra 253B v1 is better at 1 benchmark (GPQA).

Llama 3.1 Nemotron Ultra 253B v1 significantly outperforms across most benchmarks.

Mon Sep 21 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Model Size

Parameter count comparison

747.0B diff

Kimi K2 0905 has 747.0B more parameters than Llama 3.1 Nemotron Ultra 253B v1, making it 295.3% larger.

Moonshot AI
Kimi K2 0905
1.0Tparameters
NVIDIA
Llama 3.1 Nemotron Ultra 253B v1
253.0Bparameters
1000.0B
Kimi K2 0905
253.0B
Llama 3.1 Nemotron Ultra 253B v1

Context Window

Maximum input and output token capacity

Only Kimi K2 0905 specifies input context (262,144 tokens). Only Kimi K2 0905 specifies output context (262,144 tokens).

Moonshot AI
Kimi K2 0905
Input262,144 tokens
Output262,144 tokens
NVIDIA
Llama 3.1 Nemotron Ultra 253B v1
Input- tokens
Output- tokens
Mon Sep 21 2026 • llm-stats.com

License

Usage and distribution terms

Kimi K2 0905 is licensed under a proprietary license, while Llama 3.1 Nemotron Ultra 253B v1 uses Llama 3.1 Community License.

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

Kimi K2 0905

Proprietary

Closed source

Llama 3.1 Nemotron Ultra 253B v1

Llama 3.1 Community License

Open weights

Release Timeline

When each model was launched

Kimi K2 0905 was released on 2025-09-05, while Llama 3.1 Nemotron Ultra 253B v1 was released on 2025-04-07.

Kimi K2 0905 is 5 months newer than Llama 3.1 Nemotron Ultra 253B v1.

Kimi K2 0905

Sep 5, 2025

1.0 years ago

5mo newer
Llama 3.1 Nemotron Ultra 253B v1

Apr 7, 2025

1.5 years ago

Knowledge Cutoff

When training data ends

Llama 3.1 Nemotron Ultra 253B v1 has a documented knowledge cutoff of 2023-12-01, while Kimi K2 0905'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 Kimi K2 0905's cutoff date.

Kimi K2 0905

—

Llama 3.1 Nemotron Ultra 253B v1

Dec 2023

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1 side-by-side, then vote on the output you prefer.

Kimi K2 0905
✓ Preferred
Llama 3.1 Nemotron Ultra 253B v1
Open in Playground

FAQ

Common questions about Kimi K2 0905 vs Llama 3.1 Nemotron Ultra 253B v1.

Which is better, Kimi K2 0905 or Llama 3.1 Nemotron Ultra 253B v1?

Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1 are closely matched on the LLM Stats Score at 21.6 and 19.1. Kimi K2 0905 is made by Moonshot AI and Llama 3.1 Nemotron Ultra 253B v1 is made by NVIDIA. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Kimi K2 0905 compare to Llama 3.1 Nemotron Ultra 253B v1 in benchmarks?

Kimi K2 0905 scores HumanEval: 94.5%, MMLU: 90.2%, MATH: 89.1%, MMLU-Pro: 82.5%, GPQA: 75.8%. 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%.

What are the context window sizes for Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1?

Kimi K2 0905 supports 262K tokens and Llama 3.1 Nemotron Ultra 253B v1 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 Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1?

Key differences include LLM Stats Score (21.6 vs 19.1), licensing (Proprietary vs Llama 3.1 Community License). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K2 0905 and Llama 3.1 Nemotron Ultra 253B v1?

Kimi K2 0905 is developed by Moonshot AI and Llama 3.1 Nemotron Ultra 253B v1 is developed by NVIDIA.

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