What is the difference between Grok 3 and Nemotron 3 Ultra?

Grok 3 is developed by xAI while Nemotron 3 Ultra is developed by NVIDIA. Grok 3 has a 128K token context window vs Nemotron 3 Ultra's 1.0M. You can compare their actual outputs across 52 challenges on Rival to see how they differ in practice.

Which is better, Grok 3 or Nemotron 3 Ultra?

It depends on your use case. Grok 3 and Nemotron 3 Ultra each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 52 challenges so you can judge which fits your needs best.

How can I compare Grok 3 and Nemotron 3 Ultra on Rival?

This page shows a side-by-side comparison of Grok 3 and Nemotron 3 Ultra across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Jun 2026

Grok 3vsNemotron 3 Ultra

Nemotron 3 Ultra has a larger context window than Grok 3 (1.0M tokens vs 128K tokens).

Grok 3 and Nemotron 3 Ultra compared across 52 shared prompts
Spec	Grok 3	Nemotron 3 Ultra
Input price	—	Free
Output price	—	Free
Context window	128K tokens	1.0M tokens
Weights	—	Open
Free API (OpenRouter)	No	Yes (1 provider)
Released	Feb 2025	Jun 2026