Claude Haiku 4.5 vs GPT-5.4 Pro
Compare Claude Haiku 4.5 by Anthropic against GPT-5.4 Pro by OpenAI, context windows of 200K vs 1.1M, tested across 18 shared challenges.
Our Verdict
GPT-5.4 Pro
Claude Haiku 4.5Runner-up
No community votes yet. On paper, GPT-5.4 Pro has the edge — bigger model tier, newer, bigger context window.
Claude Haiku 4.5 is 36x cheaper per token — worth considering if cost matters.
Slight edge
API pricing
Cost per 1M tokens
Claude Haiku 4.5
Input
$1.00
30× cheaper
Output
$5.00
36× cheaper
GPT-5.4 Pro
Input
$30.00
Output
$180.00
Claude Haiku 4.5 is cheaper on both — 30× input, 36× output
Writing DNA
Style Comparison
Similarity
76%
Claude Haiku 4.5 uses 20.4x more emoji
Claude Haiku 4.5
GPT-5.4 Pro
61%Vocabulary50%
47wSentence Length35w
0.64Hedging0.70
5.1Bold7.5
6.3Lists8.3
0.20Emoji0.00
2.46Headings2.52
0.17Transitions0.01
Based on 24 + 12 text responses
Research
What we learned reading every model
FAQ
