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Grok 4 Fast vs Nova 2 Omni

Grok 4 Fast leads the LLM Stats Score 32.0 to 25.9.

xAI · Amazon · Updated for 2026

Which is better?

Grok 4 Fast leads the overall LLM Stats Score 32.0 to 25.9, ranking #101 overall.

In the 1 individual benchmarks reported for both models, Nova 2 Omni wins 1; 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 Grok 4 Fast

  • overall performance matters — it scores 32.0 and ranks #101 on LLM Stats

Choose Nova 2 Omni

  • you value its reported benchmark strengths — it wins 1 of 1 exact shared results
  • you want the most recent training data — it shipped Dec 2025

At a glance

The differences that matter most.

Grok 4 Fast
xAI
Nova 2 Omni
Amazon
Core performance indexes
LLM Stats Score
32.0
#101
25.9
#145
Reasoning
31.1
#103
28.2
#121
Agents
3.7
#151
4.5
#146
Cost, coverage & limits
Benchmark wins
0 of 1
1 of 1
Input price
$0.20 / M
— / M
Output price
$0.50 / M
— / M
Context window
2,000,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Grok 4 Fast
Nova 2 Omni
Math
27.4#94
25.3#106
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

7 reported for Grok 4 Fast · 18 for Nova 2 Omni

1 shared

Grok 4 Fast outperforms in 0 benchmarks, while Nova 2 Omni is better at 1 benchmark (AIME 2025).

Nova 2 Omni significantly outperforms across most benchmarks.

Fri Sep 04 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Grok 4 Fast specifies input context (2,000,000 tokens). Only Grok 4 Fast specifies output context (30,000 tokens).

xAI
Grok 4 Fast
Input2,000,000 tokens
Output30,000 tokens
Amazon
Nova 2 Omni
Input- tokens
Output- tokens
Fri Sep 04 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Grok 4 Fast and Nova 2 Omni support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Grok 4 Fast

Text
Images
Audio
Video

Nova 2 Omni

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Grok 4 Fast

Proprietary

Closed source

Nova 2 Omni

Proprietary

Closed source

Release Timeline

When each model was launched

Grok 4 Fast was released on 2025-08-28, while Nova 2 Omni was released on 2025-12-02.

Nova 2 Omni is 3 months newer than Grok 4 Fast.

Grok 4 Fast

Aug 28, 2025

1.0 years ago

Nova 2 Omni

Dec 2, 2025

9 months ago

3mo newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Grok 4 Fast and Nova 2 Omni side-by-side, then vote on the output you prefer.

Grok 4 Fast
✓ Preferred
Nova 2 Omni
Open in Playground

FAQ

Common questions about Grok 4 Fast vs Nova 2 Omni.

Which is better, Grok 4 Fast or Nova 2 Omni?

Grok 4 Fast leads the LLM Stats Score 32.0 to 25.9. Grok 4 Fast is made by xAI and Nova 2 Omni is made by Amazon. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Grok 4 Fast compare to Nova 2 Omni in benchmarks?

Grok 4 Fast scores SimpleQA: 95.0%, HMMT 2025: 93.3%, AIME 2025: 92.0%, GPQA: 85.7%, LiveCodeBench: 80.0%. Nova 2 Omni scores AIME 2025: 92.1%, RefCOCOg: 86.3%, ScreenSpot: 85.4%, MMLU-Pro: 80.7%, Tau2 Telecom: 80.0%.

What are the context window sizes for Grok 4 Fast and Nova 2 Omni?

Grok 4 Fast supports 2.0M tokens and Nova 2 Omni 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 Grok 4 Fast and Nova 2 Omni?

Key differences include LLM Stats Score (32.0 vs 25.9). See the full comparison above for benchmark-by-benchmark results.

Who makes Grok 4 Fast and Nova 2 Omni?

Grok 4 Fast is developed by xAI and Nova 2 Omni is developed by Amazon.

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