Anthropic releases Claude Sonnet 5.5, which it says is faster than Sonnet 5
2026-09-30 · that day's edition
Anthropic says Sonnet 5.5 generates outputs 30 percent or more faster than Sonnet 5, at $2 per million input tokens and $10 per million output tokens.
The API name is claude-sonnet-5-5. Anthropic says Sonnet 5.5 generates outputs 30 percent or more faster than Sonnet 5 and, in its own testing, costs up to 30 percent less per task. It reports 70.6 percent on Terminal-Bench 4.0, against 10.3 percent for Sonnet 5. These are figures from Anthropic itself.