xAI: Grok 4 vs xAI: Grok 4 Fast (free)
Compare xAI: Grok 4 and xAI: Grok 4 Fast (free), both from xAI, in 2 community votes, xai: grok 4 and xai: grok 4 fast (free) are closely matched, context windows of 256K vs 2.0M, tested across 34 shared challenges.
Our Verdict
xAI: Grok 4 Fast (free)Winner
xAI: Grok 4Runner-up
Votes are tied. xAI: Grok 4 Fast (free) is newer and likely incorporates more recent improvements.
Too close to call
API pricing
Cost per 1M tokens
xAI: Grok 4
Input
$3.00
Output
$15.00
xAI: Grok 4 Fast (free)
Input
$0.000
Output
$0.000
Writing DNA
Style Comparison
Similarity
61%
xAI: Grok 4 uses 7.0x more emoji
xAI: Grok 4
xAI: Grok 4 Fast (free)
53%Vocabulary65%
18wSentence Length13w
0.67Hedging0.56
2.7Bold1.4
2.7Lists2.5
0.07Emoji0.00
0.86Headings1.58
0.04Transitions0.28
Based on 21 + 14 text responses
Research
What we learned reading every model
FAQ
