Grok-4 Heavy vs Kimi K3.1 Pro
Kimi K3.1 Pro leads the LLM Stats Score 55.5 to 40.2.
xAI · Moonshot AI · Updated for 2026
Which is better?
Kimi K3.1 Pro leads the overall LLM Stats Score 55.5 to 40.2, ranking #5 overall.
In the 2 individual benchmarks reported for both models, Kimi K3.1 Pro 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 Grok-4 Heavy
- you are already invested in the xAI ecosystem
Choose Kimi K3.1 Pro
- overall performance matters — it scores 55.5 and ranks #5 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 2 of 2 exact shared results
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
6 reported for Grok-4 Heavy · 30 for Kimi K3.1 Pro
Grok-4 Heavy outperforms in 0 benchmarks, while Kimi K3.1 Pro is better at 2 benchmarks (GPQA, Humanity's Last Exam).
Kimi K3.1 Pro significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Context Window
Maximum input and output token capacity
Only Kimi K3.1 Pro specifies input context (1,048,576 tokens). Only Kimi K3.1 Pro specifies output context (1,048,576 tokens).
Input capabilities
Documented input modalities across available providers
Both Grok-4 Heavy and Kimi K3.1 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Grok-4 Heavy
Kimi K3.1 Pro
Release Timeline
When each model was launched
Kimi K3.1 Pro was released on 2026-10-23, while Grok-4 Heavy's release date is not specified.
We can confirm Kimi K3.1 Pro's release timeline, but cannot make a direct age comparison without Grok-4 Heavy's release date.
—
Oct 23, 2026
4 days ago
Knowledge Cutoff
When training data ends
Grok-4 Heavy has a documented knowledge cutoff of 2024-12-31, while Kimi K3.1 Pro'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 Kimi K3.1 Pro's cutoff date.
Dec 2024
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Outputs Comparison
Judge for yourself.
Run your own prompts against Grok-4 Heavy and Kimi K3.1 Pro side-by-side, then vote on the output you prefer.
FAQ
Common questions about Grok-4 Heavy vs Kimi K3.1 Pro.