Claude Sonnet 4.5
Nothing here. The model returned empty. We stared at it for a while.
Claude Sonnet 4.5 vs o1
Compare Claude Sonnet 4.5 by Anthropic against o1 by OpenAI, context windows of 200K vs 128K, tested across 43 shared challenges. Updated April 2026.
Which is better, Claude Sonnet 4.5 or o1?
Claude Sonnet 4.5 and o1 are both competitive models. Claude Sonnet 4.5 costs $3/M input tokens vs $15/M for o1. Context windows: 200K vs 128K tokens. Compare their real outputs side by side below.
Key Differences Between Claude Sonnet 4.5 and o1
Claude Sonnet 4.5 is made by anthropic while o1 is from openai. Claude Sonnet 4.5 has a 200K token context window compared to o1's 128K. On pricing, Claude Sonnet 4.5 costs $3/M input tokens vs $15/M for o1.
Our Verdict
Claude Sonnet 4.5
o1Runner-up
No community votes yet. On paper, Claude Sonnet 4.5 has the edge — bigger model tier, newer, bigger context window.
Claude Sonnet 4.5 is 4.0x cheaper per token — worth considering if cost matters.
Slight edge
Writing DNA
Style Comparison
Similarity
93%
Claude Sonnet 4.5 uses 45.2x more emoji
Claude Sonnet 4.5
o1
64%Vocabulary64%
94wSentence Length16w
0.48Hedging0.76
4.9Bold5.0
8.0Lists2.6
0.45Emoji0.00
1.91Headings0.44
0.07Transitions0.40
Based on 20 + 13 text responses
vsAsk them anything yourself
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.
Free preview13 of 58 slides
FAQ