Claude Opus 5 vs xAI: Grok 4.3
Compare Claude Opus 5 by Anthropic against xAI: Grok 4.3 by xAI, context windows of 1.0M vs 1.0M, tested across 54 shared challenges.
Our Verdict
Claude Opus 5
xAI: Grok 4.3Runner-up
No community votes yet. On paper, Claude Opus 5 has the edge — bigger model tier, newer.
xAI: Grok 4.3 is 10x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
Claude Opus 5
Input
$5.00
Output
$25.00
xAI: Grok 4.3
Input
$1.25
4.0× cheaper
Output
$2.50
10× cheaper
xAI: Grok 4.3 is cheaper on both — 4.0× input, 10× output
Writing DNA
Style Comparison
Similarity
58%
Claude Opus 5 uses 1.7x more emoji
Claude Opus 5
xAI: Grok 4.3
54%Vocabulary62%
21wSentence Length16w
0.40Hedging0.46
3.9Bold2.3
1.9Lists2.5
0.02Emoji0.00
0.71Headings0.34
0.05Transitions0.14
Based on 27 + 27 text responses
Research
What we learned reading every model
FAQ
