Key Differences
- •GPT-5.1 has a larger context window (400k vs 200k tokens)
- •Opus 4.5 has more recent training data (Mar 2025 vs Sep 2024)
- •GPT-5.1 is more affordable for input ($1.25 vs $5.00/1M tokens)
- •GPT-5.1 is more affordable for output ($10.00 vs $25.00/1M tokens)
- •Opus 4.5 is newer (released Nov 2025)
400k tokens
Context
200k tokens
Sep 2024
Knowledge
Mar 2025
Nov 2025
Released
Nov 2025
$1.25/1M
Input
$5.00/1M
$10.00/1M
Output
$25.00/1M
Both GPT-5.1 and Opus 4.5 are available on Zo Computer. Try them both to see which one works best for your use case.