xAI: Grok 4.5 vs Horizon Alpha
Compare xAI: Grok 4.5 by xAI against Horizon Alpha by OpenRouter, context windows of 500K vs 256K, tested across 33 shared challenges.
Our Verdict
xAI: Grok 4.5
Horizon AlphaRunner-up
No community votes yet. On paper, xAI: Grok 4.5 has the edge — newer, bigger context window, major provider backing.
Too close to call
API pricing
Cost per 1M tokens
xAI: Grok 4.5
Input
$2.00
Output
$6.00
Horizon Alpha
Input
$0.000
Output
$0.000
Writing DNA
Style Comparison
Similarity
76%
xAI: Grok 4.5 uses 245.4x more bold
xAI: Grok 4.5
Horizon Alpha
61%Vocabulary65%
16wSentence Length14w
0.23Hedging0.22
2.5Bold0.0
2.4Lists3.5
0.09Emoji0.00
0.48Headings0.00
0.06Transitions0.12
Based on 27 + 14 text responses
Research
What we learned reading every model
FAQ
