Grok 4.3 vs Nemotron 3 Ultra (550B A55B)
Grok 4.3 and Nemotron 3 Ultra (550B A55B) are closely matched at 22.3 and 36.3 on the LLM Stats Score. Nemotron 3 Ultra (550B A55B) is 1.7x cheaper per token.
xAI · NVIDIA · Updated for 2026
Which is better?
Grok 4.3 and Nemotron 3 Ultra (550B A55B) are closely matched on the overall LLM Stats Score at 22.3 and 36.3.
In the 1 individual benchmarks reported for both models, Grok 4.3 wins 1; this is a narrower head-to-head signal than the composite indexes.
On price, Nemotron 3 Ultra (550B A55B) is roughly 1.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Grok 4.3 also accepts a larger context window (1,000,000 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 Grok 4.3
- you value its reported benchmark strengths — it wins 1 of 1 exact shared results
- you process long inputs — it offers a 1,000,000 token context window
Choose Nemotron 3 Ultra (550B A55B)
- cost matters — it's about 1.7x cheaper per token
- you want the most recent training data — it shipped Jun 2026
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Individual benchmarks
1 reported for Grok 4.3 · 26 for Nemotron 3 Ultra (550B A55B)
Grok 4.3 outperforms in 1 benchmarks (Finance Agent v2), while Nemotron 3 Ultra (550B A55B) is better at 0 benchmarks.
Grok 4.3 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, Grok 4.3 ($1.25/1M tokens) is 2.5x more expensive than Nemotron 3 Ultra (550B A55B) ($0.50/1M tokens).
For output processing, Grok 4.3 ($2.50/1M tokens) is 1.1x more expensive than Nemotron 3 Ultra (550B A55B) ($2.20/1M tokens).
In conclusion, Grok 4.3 is more expensive than Nemotron 3 Ultra (550B A55B).*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Grok 4.3 accepts 1,000,000 input tokens compared to Nemotron 3 Ultra (550B A55B)'s 262,144 tokens. Only Nemotron 3 Ultra (550B A55B) specifies output context (262,144 tokens).
License
Usage and distribution terms
Grok 4.3 is licensed under a proprietary 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.
Proprietary
Closed source
OpenMDW License v1.1
Open weights
Release Timeline
When each model was launched
Grok 4.3 was released on 2026-05-06, while Nemotron 3 Ultra (550B A55B) was released on 2026-06-04.
Nemotron 3 Ultra (550B A55B) is 1 month newer than Grok 4.3.
May 6, 2026
4 months ago
Jun 4, 2026
3 months ago
4w newerKnowledge Cutoff
When training data ends
Nemotron 3 Ultra (550B A55B) has a documented knowledge cutoff of 2025-09-30, while Grok 4.3'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 Grok 4.3's cutoff date.
—
Sep 2025
Provider Availability
Grok 4.3 is available from xAI. Nemotron 3 Ultra (550B A55B) is available from DeepInfra.
Grok 4.3
Nemotron 3 Ultra (550B A55B)
Outputs Comparison
Judge for yourself.
Run your own prompts against Grok 4.3 and Nemotron 3 Ultra (550B A55B) side-by-side, then vote on the output you prefer.
FAQ
Common questions about Grok 4.3 vs Nemotron 3 Ultra (550B A55B).