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Gemini 3 Flash vs Grok-4 Heavy

Grok-4 Heavy leads the LLM Stats Score 40.7 to 36.7.

Google · xAI · Updated for 2026

Which is better?

Grok-4 Heavy leads the overall LLM Stats Score 40.7 to 36.7, ranking #71 overall.

In the 3 individual benchmarks reported for both models, Grok-4 Heavy wins 2; 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 Gemini 3 Flash

  • you want predictable pricing at $0.50/M input and $3.00/M output

Choose Grok-4 Heavy

  • overall performance matters — it scores 40.7 and ranks #71 on LLM Stats
  • you value its reported benchmark strengths — it wins 2 of 3 exact shared results

At a glance

The differences that matter most.

Gemini 3 Flash
Google
Grok-4 Heavy
xAI
Core performance indexes
LLM Stats Score
36.7
#93
40.7
#71
Reasoning
37.6
#83
39.0
#73
Coding
22.2
#98
17.6
#134
Cost, coverage & limits
Benchmark wins
1 of 3
2 of 3
Input price
$0.50 / M
— / M
Output price
$3.00 / M
— / M
Context window
1,000,000
—

Capability indexes

Additional strengths measured across groups of related public benchmarks

1 shared
Index
Gemini 3 Flash
Grok-4 Heavy
Math
37.2#34
41.7#8
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

24 reported for Gemini 3 Flash · 6 for Grok-4 Heavy

3 shared

Gemini 3 Flash outperforms in 1 benchmarks (GPQA), while Grok-4 Heavy is better at 2 benchmarks (AIME 2025, Humanity's Last Exam).

Grok-4 Heavy shows notably better performance in the majority of benchmarks.

Mon Oct 19 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only Gemini 3 Flash specifies input context (1,000,000 tokens). Only Gemini 3 Flash specifies output context (65,536 tokens).

Google
Gemini 3 Flash
Input1,000,000 tokens
Output65,536 tokens
xAI
Grok-4 Heavy
Input- tokens
Output- tokens
Mon Oct 19 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Gemini 3 Flash and Grok-4 Heavy support multimodal inputs.

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

Gemini 3 Flash

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 Flash

Proprietary

Closed source

Grok-4 Heavy

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3 Flash was released on 2025-12-17, while Grok-4 Heavy's release date is not specified.

We can confirm Gemini 3 Flash's release timeline, but cannot make a direct age comparison without Grok-4 Heavy's release date.

Gemini 3 Flash

Dec 17, 2025

10 months ago

Grok-4 Heavy

—

Knowledge Cutoff

When training data ends

Gemini 3 Flash has a knowledge cutoff of 2025-01-31, while Grok-4 Heavy has a cutoff of 2024-12-31.

Gemini 3 Flash has more recent training data (up to 2025-01-31), making it potentially better informed about events through that date compared to Grok-4 Heavy (2024-12-31).

Gemini 3 Flash

Jan 2025

1 mo newer
Grok-4 Heavy

Dec 2024

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Gemini 3 Flash and Grok-4 Heavy side-by-side, then vote on the output you prefer.

Gemini 3 Flash
✓ Preferred
Grok-4 Heavy
Open in Playground

FAQ

Common questions about Gemini 3 Flash vs Grok-4 Heavy.

Which is better, Gemini 3 Flash or Grok-4 Heavy?

Grok-4 Heavy leads the LLM Stats Score 40.7 to 36.7. Gemini 3 Flash 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 Flash compare to Grok-4 Heavy in benchmarks?

Gemini 3 Flash scores Vending-Bench 2: 100.0%, AIME 2025: 99.7%, Global PIQA: 92.8%, MMMLU: 91.8%, GPQA: 90.4%. Grok-4 Heavy scores AIME 2025: 100.0%, HMMT25: 96.7%, GPQA: 88.4%, LiveCodeBench: 79.4%, USAMO25: 61.9%.

What are the context window sizes for Gemini 3 Flash and Grok-4 Heavy?

Gemini 3 Flash supports 1.0M tokens and Grok-4 Heavy 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 Gemini 3 Flash and Grok-4 Heavy?

Key differences include LLM Stats Score (36.7 vs 40.7). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3 Flash and Grok-4 Heavy?

Gemini 3 Flash is developed by Google and Grok-4 Heavy is developed by xAI.

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