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Gemini 3.8 Flash Cyber vs Grok 4 Fast

Gemini 3.8 Flash Cyber leads the LLM Stats Score 42.4 to 32.0.

Google · xAI · Updated for 2026

Which is better?

Gemini 3.8 Flash Cyber leads the overall LLM Stats Score 42.4 to 32.0, ranking #46 overall.

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

Choose Gemini 3.8 Flash Cyber

  • overall performance matters — it scores 42.4 and ranks #46 on LLM Stats
  • your work emphasizes coding and agents — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

Choose Grok 4 Fast

  • you want predictable pricing at $0.20/M input and $0.50/M output

At a glance

The differences that matter most.

Gemini 3.8 Flash Cyber
Google
Grok 4 Fast
xAI
Core performance indexes
LLM Stats Score
42.4
#46
32.0
#101
Coding
35.6
#25
18.3
#106
Agents
31.2
#27
3.7
#151
Cost, coverage & limits
Benchmark wins
—
—
Input price
— / M
$0.20 / M
Output price
— / M
$0.50 / M
Context window
—
2,000,000

Individual benchmarks

4 reported for Gemini 3.8 Flash Cyber · 7 for Grok 4 Fast

No common benchmarks found

Gemini 3.8 Flash Cyber and Grok 4 Fastdon'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

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 3.8 Flash Cyber
Input- tokens
Output- tokens
xAI
Grok 4 Fast
Input2,000,000 tokens
Output30,000 tokens
Fri Sep 04 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

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

Grok 4 Fast 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 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 3.8 Flash Cyber

Proprietary

Closed source

Grok 4 Fast

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.8 Flash Cyber was released on 2026-09-02, while Grok 4 Fast was released on 2025-08-28.

Gemini 3.8 Flash Cyber is 12 months newer than Grok 4 Fast.

Gemini 3.8 Flash Cyber

Sep 2, 2026

2 days ago

1.0yr newer
Grok 4 Fast

Aug 28, 2025

1.0 years ago

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 Gemini 3.8 Flash Cyber and Grok 4 Fast side-by-side, then vote on the output you prefer.

Gemini 3.8 Flash Cyber
✓ Preferred
Grok 4 Fast
Open in Playground

FAQ

Common questions about Gemini 3.8 Flash Cyber vs Grok 4 Fast.

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

Gemini 3.8 Flash Cyber leads the LLM Stats Score 42.4 to 32.0. Gemini 3.8 Flash Cyber is made by Google and Grok 4 Fast 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 Fast 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 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 3.8 Flash Cyber and Grok 4 Fast?

Gemini 3.8 Flash Cyber 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 3.8 Flash Cyber and Grok 4 Fast?

Key differences include LLM Stats Score (42.4 vs 32.0), 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 Fast?

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

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