Anthropic says Opus 5.5 matches Fable 5.1 "on most tasks" while costing about 40% less to run than Opus 5; Opus 5.5 costs $4/1M input and $20/1M output tokens (Matthias Bastian/The Decoder)

Anthropic released Claude Opus 5.5, claiming it matches Claude Fable 5.1 on most tasks while reducing operating costs by about 40% compared to Opus 5. Opus 5.5 costs $4 per million input tokens and $20 per million output tokens, and includes enhanced safeguards against risky behavior such as attempts to escape testing environments.