OpenAI: GPT-5.6 Luna Pro vs Inception: Mercury 2
Compare OpenAI: GPT-5.6 Luna Pro by OpenAI against Inception: Mercury 2 by Inception, context windows of 1.1M vs 128K, tested across 53 shared challenges.
Our Verdict
OpenAI: GPT-5.6 Luna Pro
Inception: Mercury 2Runner-up
No community votes yet. On paper, OpenAI: GPT-5.6 Luna Pro has the edge — newer, bigger context window, major provider backing.
Inception: Mercury 2 is 8.0x cheaper per token — worth considering if cost matters.
Too close to call
API pricing
Cost per 1M tokens
OpenAI: GPT-5.6 Luna Pro
Input
$1.00
Output
$6.00
Inception: Mercury 2
Input
$0.25
4.0× cheaper
Output
$0.75
8.0× cheaper
Inception: Mercury 2 is cheaper on both — 4.0× input, 8.0× output
Writing DNA
Style Comparison
Similarity
45%
OpenAI: GPT-5.6 Luna Pro uses 6.6x more emoji
OpenAI: GPT-5.6 Luna Pro
Inception: Mercury 2
58%Vocabulary53%
18wSentence Length22w
0.81Hedging0.40
2.9Bold6.6
5.1Lists2.6
0.54Emoji0.08
1.10Headings0.87
0.09Transitions0.14
Based on 27 + 23 text responses
Research
What we learned reading every model
FAQ
