Anthropic Ships Claude Sonnet 5.5 — 30% Faster, 30% Cheaper Than Sonnet 5
Anthropic released Claude Sonnet 5.5 on September 28, 2026 — the second model in the Claude 5.5 family, running 30% faster and costing up to 30% less per task than Sonnet 5, at the same $2/M rate card.