Grok 4.1 Fast vs OpenAI o4-mini
Compare Grok 4.1 Fast by xAI against OpenAI o4-mini by OpenAI, tested across 54 shared challenges. Updated June 2026.
Which is better, Grok 4.1 Fast or OpenAI o4-mini?
Grok 4.1 Fast and OpenAI o4-mini are both competitive models. Compare their real outputs side by side below.
Key Differences Between Grok 4.1 Fast and OpenAI o4-mini
Grok 4.1 Fast is made by xai while OpenAI o4-mini is from openai.
Our Verdict
Grok 4.1 Fast
OpenAI o4-miniRunner-up
No community votes yet. On paper, Grok 4.1 Fast has the edge — bigger model tier, newer.
Too close to call
API pricing
Cost per 1M tokens
Grok 4.1 Fast
Input
—
Output
—
OpenAI o4-mini
Input
$1.10
Output
$4.40
Writing DNA
Style Comparison
Similarity
52%
Grok 4.1 Fast uses 466.5x more bold
Grok 4.1 Fast
OpenAI o4-mini
67%Vocabulary73%
15wSentence Length15w
0.17Hedging0.18
4.7Bold0.0
3.7Lists2.1
0.00Emoji0.00
0.99Headings0.00
0.14Transitions0.02
Based on 24 + 10 text responses
Research
What we learned reading every model
FAQ
