Claude Opus 5 vs xAI: Grok 4
Compare Claude Opus 5 by Anthropic against xAI: Grok 4 by xAI, context windows of 1.0M vs 256K, tested across 53 shared challenges.
Our Verdict
Claude Opus 5
xAI: Grok 4Runner-up
No community votes yet. On paper, Claude Opus 5 has the edge — bigger model tier, newer, bigger context window.
Slight edge
API pricing
Cost per 1M tokens
Claude Opus 5
Input
$5.00
Output
$25.00
xAI: Grok 4
Input
$3.00
1.7× cheaper
Output
$15.00
1.7× cheaper
xAI: Grok 4 is cheaper on both — 1.7× input, 1.7× output
Writing DNA
Style Comparison
Similarity
52%
xAI: Grok 4 uses 4.1x more emoji
Claude Opus 5
xAI: Grok 4
54%Vocabulary53%
21wSentence Length18w
0.40Hedging0.67
3.9Bold2.7
1.9Lists2.7
0.02Emoji0.07
0.71Headings0.86
0.05Transitions0.04
Based on 27 + 21 text responses
Research
What we learned reading every model
FAQ
