Claude Sonnet 4.6 vs OpenAI: GPT-5.6 Luna Pro
Compare Claude Sonnet 4.6 by Anthropic against OpenAI: GPT-5.6 Luna Pro by OpenAI, context windows of 1.0M vs 1.1M, tested across 53 shared challenges.
Our Verdict
Claude Sonnet 4.6
OpenAI: GPT-5.6 Luna Pro
No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.
Too close to call
API pricing
Cost per 1M tokens
Claude Sonnet 4.6
Input
$3.00
Output
$15.00
OpenAI: GPT-5.6 Luna Pro
Input
$1.00
3.0× cheaper
Output
$6.00
2.5× cheaper
OpenAI: GPT-5.6 Luna Pro is cheaper on both — 3.0× input, 2.5× output
Writing DNA
Style Comparison
Similarity
48%
OpenAI: GPT-5.6 Luna Pro uses 4.5x more transitions
Claude Sonnet 4.6
OpenAI: GPT-5.6 Luna Pro
56%Vocabulary58%
36wSentence Length18w
0.53Hedging0.81
5.1Bold2.9
3.4Lists5.1
0.19Emoji0.54
2.10Headings1.10
0.02Transitions0.09
Based on 23 + 27 text responses
Research
What we learned reading every model
FAQ
