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Gemini 3.8 Flash Cyber vs Grok-4 Heavy

Gemini 3.8 Flash Cyber and Grok-4 Heavy are closely matched at 42.4 and 40.9 on the LLM Stats Score.

Google · xAI · Updated for 2026

Which is better?

Gemini 3.8 Flash Cyber and Grok-4 Heavy are closely matched on the overall LLM Stats Score at 42.4 and 40.9.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Gemini 3.8 Flash Cyber

  • your work emphasizes coding — it leads those capability indexes

Choose Grok-4 Heavy

  • you are already invested in the xAI ecosystem

At a glance

The differences that matter most.

Gemini 3.8 Flash Cyber
Google
Grok-4 Heavy
xAI
Core performance indexes
LLM Stats Score
42.4
#46
40.9
#50
Coding
35.6
#25
17.9
#108
Cost, coverage & limits
Benchmark wins
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—
Input price
— / M
— / M
Output price
— / M
— / M
Context window
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Individual benchmarks

4 reported for Gemini 3.8 Flash Cyber · 6 for Grok-4 Heavy

No common benchmarks found

Gemini 3.8 Flash Cyber and Grok-4 Heavydon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Input capabilities

Documented input modalities across available providers

Grok-4 Heavy supports multimodal inputs, whereas Gemini 3.8 Flash Cyber does not.

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

Gemini 3.8 Flash Cyber

Text
Images
Audio
Video

Grok-4 Heavy

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 3.8 Flash Cyber

Proprietary

Closed source

Grok-4 Heavy

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.8 Flash Cyber was released on 2026-09-02, while Grok-4 Heavy's release date is not specified.

We can confirm Gemini 3.8 Flash Cyber's release timeline, but cannot make a direct age comparison without Grok-4 Heavy's release date.

Gemini 3.8 Flash Cyber

Sep 2, 2026

2 days ago

Grok-4 Heavy

—

Knowledge Cutoff

When training data ends

Grok-4 Heavy has a documented knowledge cutoff of 2024-12-31, while Gemini 3.8 Flash Cyber's cutoff date is not specified.

We can confirm Grok-4 Heavy's training data extends to 2024-12-31, but cannot make a direct comparison without Gemini 3.8 Flash Cyber's cutoff date.

Gemini 3.8 Flash Cyber

—

Grok-4 Heavy

Dec 2024

Outputs Comparison

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Judge for yourself.

Run your own prompts against Gemini 3.8 Flash Cyber and Grok-4 Heavy side-by-side, then vote on the output you prefer.

Gemini 3.8 Flash Cyber
✓ Preferred
Grok-4 Heavy
Open in Playground

FAQ

Common questions about Gemini 3.8 Flash Cyber vs Grok-4 Heavy.

Which is better, Gemini 3.8 Flash Cyber or Grok-4 Heavy?

Gemini 3.8 Flash Cyber and Grok-4 Heavy are closely matched on the LLM Stats Score at 42.4 and 40.9. Gemini 3.8 Flash Cyber is made by Google and Grok-4 Heavy is made by xAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Gemini 3.8 Flash Cyber compare to Grok-4 Heavy in benchmarks?

Gemini 3.8 Flash Cyber scores Gray Swan IPI Benchmark: 94.0%, CyberGym: 86.2%, Google Real-world Vulnerability Discovery: 71.0%, CWE-Bench: 47.2%. Grok-4 Heavy scores AIME 2025: 100.0%, HMMT25: 96.7%, GPQA: 88.4%, LiveCodeBench: 79.4%, USAMO25: 61.9%.

What are the main differences between Gemini 3.8 Flash Cyber and Grok-4 Heavy?

Key differences include LLM Stats Score (42.4 vs 40.9), multimodal support (no vs yes). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.8 Flash Cyber and Grok-4 Heavy?

Gemini 3.8 Flash Cyber is developed by Google and Grok-4 Heavy is developed by xAI.

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