ComparisonClaude Sonnet 4.5 vs Sonnet 5.5: What Changes If You Switch
Sonnet 4.5 retires Nov 30, 2026. Here's how Sonnet 5.5 compares on price, context window, benchmarks, speed, and availability — and what breaks in your code.
NewsClaude Sonnet 4.5 Retirement: What the November 30 Date Means
Anthropic deprecated Claude Sonnet 4.5 on September 30, 2026, with a tentative November 30 retirement date. Here is what changes, and how to migrate.