Model Comparison

Gemini Diffusion vs Grok 4 Fast

Grok 4 Fast significantly outperforms across most benchmarks.

Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

3 benchmarks

Gemini Diffusion outperforms in 0 benchmarks, while Grok 4 Fast is better at 3 benchmarks (AIME 2025, GPQA, LiveCodeBench).

Grok 4 Fast significantly outperforms across most benchmarks.

Tue May 26 2026 • llm-stats.com

Arena Performance

Human preference votes

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).

Google
Gemini Diffusion
Input- tokens
Output- tokens
xAI
Grok 4 Fast
Input2,000,000 tokens
Output30,000 tokens
Tue May 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Grok 4 Fast supports multimodal inputs, whereas Gemini Diffusion does not.

Grok 4 Fast can handle both text and other forms of data like images, making it suitable for multimodal applications.

Gemini Diffusion

Text
Images
Audio
Video

Grok 4 Fast

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.

Gemini Diffusion

Proprietary

Closed source

Grok 4 Fast

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini Diffusion was released on 2025-05-20, while Grok 4 Fast was released on 2025-08-28.

Grok 4 Fast is 3 months newer than Gemini Diffusion.

Gemini Diffusion

May 20, 2025

1.0 years ago

Grok 4 Fast

Aug 28, 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→

Key Takeaways

Google

No standout differentiators in the data we have for this pair.

xAI
Larger context window (2,000,000 tokens)
Supports multimodal inputs
Higher AIME 2025 score (92.0% vs 23.3%)
Higher GPQA score (85.7% vs 40.4%)
Higher LiveCodeBench score (80.0% vs 30.9%)

Detailed Comparison

AI Model Comparison Table
Feature
Google
Gemini Diffusion
xAI
Grok 4 Fast

FAQ

Common questions about Gemini Diffusion vs Grok 4 Fast.

Which is better, Gemini Diffusion or Grok 4 Fast?

Grok 4 Fast significantly outperforms across most benchmarks. Gemini Diffusion is made by Google and Grok 4 Fast is made by xAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Gemini Diffusion compare to Grok 4 Fast in benchmarks?

Gemini Diffusion scores HumanEval: 89.6%, MBPP: 76.0%, Global-MMLU-Lite: 69.1%, LBPP (v2): 56.8%, BigCodeBench: 45.4%. Grok 4 Fast scores SimpleQA: 95.0%, HMMT 2025: 93.3%, AIME 2025: 92.0%, GPQA: 85.7%, LiveCodeBench: 80.0%.

What are the context window sizes for Gemini Diffusion and Grok 4 Fast?

Gemini Diffusion supports an unknown number of tokens and Grok 4 Fast supports 2.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini Diffusion and Grok 4 Fast?

Key differences include multimodal support (no vs yes). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini Diffusion and Grok 4 Fast?

Gemini Diffusion is developed by Google and Grok 4 Fast is developed by xAI.