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Kimi-k1.5 vs Llama 3.1 Nemotron Ultra 253B v1

Kimi-k1.5 and Llama 3.1 Nemotron Ultra 253B v1 are closely matched at 17.2 and 19.1 on the LLM Stats Score.

Moonshot AI · NVIDIA · Updated for 2026

Which is better?

Kimi-k1.5 and Llama 3.1 Nemotron Ultra 253B v1 are closely matched on the overall LLM Stats Score at 17.2 and 19.1.

In the 2 individual benchmarks reported for both models, Llama 3.1 Nemotron Ultra 253B v1 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 Kimi-k1.5

  • you are already invested in the Moonshot AI ecosystem

Choose Llama 3.1 Nemotron Ultra 253B v1

  • you value its reported benchmark strengths — it wins 2 of 2 exact shared results
  • you want the most recent training data — it shipped Apr 2025
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Kimi-k1.5
Moonshot AI
Llama 3.1 Nemotron Ultra 253B v1
NVIDIA
Core performance indexes
LLM Stats Score
17.2
#218
19.1
#206
Reasoning
16.4
#215
18.8
#205
Cost, coverage & limits
Benchmark wins
0 of 2
2 of 2
Input price
— / M
— / M
Output price
— / M
— / M
Context window
—
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Kimi-k1.5
Llama 3.1 Nemotron Ultra 253B v1
Math
20.2#160
15.6#215
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

9 reported for Kimi-k1.5 · 6 for Llama 3.1 Nemotron Ultra 253B v1

2 shared

Kimi-k1.5 outperforms in 0 benchmarks, while Llama 3.1 Nemotron Ultra 253B v1 is better at 2 benchmarks (IFEval, MATH-500).

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

Input capabilities

Documented input modalities across available providers

Kimi-k1.5 supports multimodal inputs, whereas Llama 3.1 Nemotron Ultra 253B v1 does not.

Kimi-k1.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Kimi-k1.5

Text
Images
Audio
Video

Llama 3.1 Nemotron Ultra 253B v1

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi-k1.5 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-k1.5

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-k1.5 was released on 2025-01-20, while Llama 3.1 Nemotron Ultra 253B v1 was released on 2025-04-07.

Llama 3.1 Nemotron Ultra 253B v1 is 3 months newer than Kimi-k1.5.

Kimi-k1.5

Jan 20, 2025

1.7 years ago

Llama 3.1 Nemotron Ultra 253B v1

Apr 7, 2025

1.5 years ago

2mo newer

Knowledge Cutoff

When training data ends

Llama 3.1 Nemotron Ultra 253B v1 has a documented knowledge cutoff of 2023-12-01, while Kimi-k1.5'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 Kimi-k1.5's cutoff date.

Kimi-k1.5

—

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-k1.5 and Llama 3.1 Nemotron Ultra 253B v1 side-by-side, then vote on the output you prefer.

Kimi-k1.5
✓ Preferred
Llama 3.1 Nemotron Ultra 253B v1
Open in Playground

FAQ

Common questions about Kimi-k1.5 vs Llama 3.1 Nemotron Ultra 253B v1.

Which is better, Kimi-k1.5 or Llama 3.1 Nemotron Ultra 253B v1?

Kimi-k1.5 and Llama 3.1 Nemotron Ultra 253B v1 are closely matched on the LLM Stats Score at 17.2 and 19.1. Kimi-k1.5 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-k1.5 compare to Llama 3.1 Nemotron Ultra 253B v1 in benchmarks?

Kimi-k1.5 scores MATH-500: 96.2%, CLUEWSC: 91.4%, C-Eval: 88.3%, MMLU: 87.4%, IFEval: 87.2%. 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 main differences between Kimi-k1.5 and Llama 3.1 Nemotron Ultra 253B v1?

Key differences include LLM Stats Score (17.2 vs 19.1), multimodal support (yes vs no), licensing (Proprietary vs Llama 3.1 Community License). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi-k1.5 and Llama 3.1 Nemotron Ultra 253B v1?

Kimi-k1.5 is developed by Moonshot AI and Llama 3.1 Nemotron Ultra 253B v1 is developed by NVIDIA.

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