Claude Sonnet 4.5 vs Claude Opus 4.8
Compare Claude Sonnet 4.5 and Claude Opus 4.8, both from Anthropic, context windows of 200K vs 1.0M, tested across 42 shared challenges.
Our Verdict
Claude Opus 4.8
Claude Sonnet 4.5Runner-up
No community votes yet. On paper, Claude Opus 4.8 has the edge — bigger model tier, newer, bigger context window.
Slight edge
API pricing
Cost per 1M tokens
Claude Sonnet 4.5
Input
$3.00
1.7× cheaper
Output
$15.00
1.7× cheaper
Claude Opus 4.8
Input
$5.00
Output
$25.00
Claude Sonnet 4.5 is cheaper on both — 1.7× input, 1.7× output
Writing DNA
Style Comparison
Similarity
57%
Claude Sonnet 4.5 uses 5.0x more sentence length
Claude Sonnet 4.5
Claude Opus 4.8
64%Vocabulary60%
94wSentence Length19w
0.48Hedging0.46
4.9Bold4.7
8.0Lists3.2
0.45Emoji0.78
1.91Headings1.15
0.07Transitions0.04
Based on 20 + 27 text responses
Research
What we learned reading every model
FAQ
