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Kimi K3 vs Nemotron 3 Ultra (550B A55B)

Kimi K3 leads the LLM Stats Score 53.8 to 36.3.

Moonshot AI · NVIDIA · Updated for 2026

Which is better?

Kimi K3 leads the overall LLM Stats Score 53.8 to 36.3, ranking #8 overall.

In the 4 individual benchmarks reported for both models, Kimi K3 wins 4; 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 K3

  • overall performance matters — it scores 53.8 and ranks #8 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 4 of 4 exact shared results
  • you want the most recent training data — it shipped Jul 2026

Choose Nemotron 3 Ultra (550B A55B)

  • you are already invested in the NVIDIA ecosystem

At a glance

The differences that matter most.

Kimi K3
Moonshot AI
Nemotron 3 Ultra (550B A55B)
NVIDIA
Core performance indexes
LLM Stats Score
53.8
#8
36.3
#74
Reasoning
52.6
#8
35.4
#76
Coding
43.4
#5
21.3
#84
Agents
39.1
#8
11.7
#98
Cost, coverage & limits
Benchmark wins
4 of 4
0 of 4
Input price
$3.00 / M
— / M
Output price
$15.00 / M
— / M
Context window
1,048,576
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Kimi K3
Nemotron 3 Ultra (550B A55B)
Math
40.6#11
36.2#38
Tool use
34.1#3
3.7#154
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

31 reported for Kimi K3 · 26 for Nemotron 3 Ultra (550B A55B)

4 shared

Kimi K3 outperforms in 4 benchmarks (BrowseComp, GPQA, Humanity's Last Exam, Terminal-Bench 2.1), while Nemotron 3 Ultra (550B A55B) is better at 0 benchmarks.

Kimi K3 significantly outperforms across most benchmarks.

Sun Sep 06 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Model Size

Parameter count comparison

2250.0B diff

Kimi K3 has 2250.0B more parameters than Nemotron 3 Ultra (550B A55B), making it 409.1% larger.

Moonshot AI
Kimi K3
2.8Tparameters
NVIDIA
Nemotron 3 Ultra (550B A55B)
550.0Bparameters
2800.0B
Kimi K3
550.0B
Nemotron 3 Ultra (550B A55B)

Context Window

Maximum input and output token capacity

Only Kimi K3 specifies input context (1,048,576 tokens). Only Kimi K3 specifies output context (1,048,576 tokens).

Moonshot AI
Kimi K3
Input1,048,576 tokens
Output1,048,576 tokens
NVIDIA
Nemotron 3 Ultra (550B A55B)
Input- tokens
Output- tokens
Sun Sep 06 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Kimi K3 supports multimodal inputs, whereas Nemotron 3 Ultra (550B A55B) does not.

Kimi K3 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Kimi K3

Text
Images
Audio
Video

Nemotron 3 Ultra (550B A55B)

Text
Images
Audio
Video

License

Usage and distribution terms

Kimi K3 is licensed under Kimi K3 License, while Nemotron 3 Ultra (550B A55B) uses OpenMDW License v1.1.

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

Kimi K3

Kimi K3 License

Open weights

Nemotron 3 Ultra (550B A55B)

OpenMDW License v1.1

Open weights

Release Timeline

When each model was launched

Kimi K3 was released on 2026-07-16, while Nemotron 3 Ultra (550B A55B) was released on 2026-06-04.

Kimi K3 is 1 month newer than Nemotron 3 Ultra (550B A55B).

Kimi K3

Jul 16, 2026

1 months ago

1mo newer
Nemotron 3 Ultra (550B A55B)

Jun 4, 2026

3 months ago

Knowledge Cutoff

When training data ends

Nemotron 3 Ultra (550B A55B) has a documented knowledge cutoff of 2025-09-30, while Kimi K3's cutoff date is not specified.

We can confirm Nemotron 3 Ultra (550B A55B)'s training data extends to 2025-09-30, but cannot make a direct comparison without Kimi K3's cutoff date.

Kimi K3

—

Nemotron 3 Ultra (550B A55B)

Sep 2025

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Kimi K3 and Nemotron 3 Ultra (550B A55B) side-by-side, then vote on the output you prefer.

Kimi K3
✓ Preferred
Nemotron 3 Ultra (550B A55B)
Open in Playground

FAQ

Common questions about Kimi K3 vs Nemotron 3 Ultra (550B A55B).

Which is better, Kimi K3 or Nemotron 3 Ultra (550B A55B)?

Kimi K3 leads the LLM Stats Score 53.8 to 36.3. Kimi K3 is made by Moonshot AI and Nemotron 3 Ultra (550B A55B) 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 K3 compare to Nemotron 3 Ultra (550B A55B) in benchmarks?

Kimi K3 scores MathVision: 97.8%, DeepSearchQA: 95.0%, GPQA: 93.5%, CharXiv-R: 91.3%, BrowseComp: 91.2%. Nemotron 3 Ultra (550B A55B) scores RULER: 94.7%, IMO-AnswerBench: 92.3%, PinchBench: 90.0%, LiveCodeBench v6: 89.0%, GPQA: 87.0%.

What are the context window sizes for Kimi K3 and Nemotron 3 Ultra (550B A55B)?

Kimi K3 supports 1.0M tokens and Nemotron 3 Ultra (550B A55B) 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 K3 and Nemotron 3 Ultra (550B A55B)?

Key differences include LLM Stats Score (53.8 vs 36.3), multimodal support (yes vs no), licensing (Kimi K3 License vs OpenMDW License v1.1). See the full comparison above for benchmark-by-benchmark results.

Who makes Kimi K3 and Nemotron 3 Ultra (550B A55B)?

Kimi K3 is developed by Moonshot AI and Nemotron 3 Ultra (550B A55B) is developed by NVIDIA.

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