Compare
Claude Opus 5 vs Claude Sonnet 4.6
Input, output, and cached reads all scale by the same multiple between these two, so Claude Sonnet 4.6 comes out 1.7× cheaper on every shape below — not just some of them. No traffic pattern flips this one.
Per million tokens
Claude Opus 5
Claude Sonnet 4.6
Monthly cost by workload
Chat assistant
60,000 requests · 1,200 in / 400 out · 30% cached — short prompts, short answers, high volume
Claude Opus 5
$862.80
Claude Sonnet 4.6
$517.68
Claude Sonnet 4.6 is 1.7× cheaper on this shape — $345.12 a month.
RAG over documents
20,000 requests · 18,000 in / 700 out · 75% cached — large retrieved context, heavily cached prefix
Claude Opus 5
$935.00
Claude Sonnet 4.6
$561.00
Claude Sonnet 4.6 is 1.7× cheaper on this shape — $374.00 a month.
Coding agent
4,000 requests · 45,000 in / 6,000 out · 80% cached — long tool-calling loops, big cached prefix
Claude Opus 5
$852.00
Claude Sonnet 4.6
$511.20
Claude Sonnet 4.6 is 1.7× cheaper on this shape — $340.80 a month.