AIAnthropic releases Claude Opus 5.5
Anthropic says the first model in its Claude 5.5 family performs at Claude Fable 5.1’s level for most tasks and costs 40% less to run than Opus 5.
TLDR
Anthropic announced Claude Opus 5.5’s availability on September 22, 2026. It describes the model as the first in the Claude 5.5 family, with Claude Fable 5.1-level performance for most tasks and a 40% lower running cost than Opus 5. Factory says Opus 5.5 is also live on its platform; its initial observations include 20–25% fewer output tokens than Opus 5 at the same effort.
Anthropic releases Claude Opus 5.5
Anthropic says the first model in its Claude 5.5 family performs at Claude Fable 5.1’s level for most tasks and costs 40% less to run than Opus 5.
