Kimi K3 vs Nemotron 3 Ultra (550B A55B)
Kimi K3 leads the LLM Stats Score 53.0 to 36.3. Nemotron 3 Ultra (550B A55B) is 6.2x cheaper per token.
Moonshot AI · NVIDIA · Updated for 2026
Which is better?
Kimi K3 leads the overall LLM Stats Score 53.0 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.
On price, Nemotron 3 Ultra (550B A55B) is roughly 6.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Kimi K3 also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Kimi K3
- overall performance matters — it scores 53.0 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 process long inputs — it offers a 1,048,576 token context window
- you want the most recent training data — it shipped Jul 2026
Choose Nemotron 3 Ultra (550B A55B)
- cost matters — it's about 6.2x cheaper per token
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
31 reported for Kimi K3 · 26 for Nemotron 3 Ultra (550B A55B)
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.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Kimi K3 ($2.85/1M tokens) is 5.7x more expensive than Nemotron 3 Ultra (550B A55B) ($0.50/1M tokens).
For output processing, Kimi K3 ($14.25/1M tokens) is 6.5x more expensive than Nemotron 3 Ultra (550B A55B) ($2.20/1M tokens).
In conclusion, Kimi K3 is more expensive than Nemotron 3 Ultra (550B A55B).*
* Using a 3:1 ratio of input to output tokens
Model Size
Parameter count comparison
Kimi K3 has 2250.0B more parameters than Nemotron 3 Ultra (550B A55B), making it 409.1% larger.
Context Window
Maximum input and output token capacity
Kimi K3 accepts 1,048,576 input tokens compared to Nemotron 3 Ultra (550B A55B)'s 262,144 tokens. Kimi K3 can generate longer responses up to 1,048,576 tokens, while Nemotron 3 Ultra (550B A55B) is limited to 262,144 tokens.
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
Nemotron 3 Ultra (550B A55B)
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 License
Open weights
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).
Jul 16, 2026
2 months ago
1mo newerJun 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.
—
Sep 2025
Provider Availability
Kimi K3 is available from DeepInfra, Fireworks, Moonshot AI, Novita, Together. Nemotron 3 Ultra (550B A55B) is available from DeepInfra.
Kimi K3
Nemotron 3 Ultra (550B A55B)
Outputs Comparison
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.
FAQ
Common questions about Kimi K3 vs Nemotron 3 Ultra (550B A55B).