Claude Sonnet 5 migration: the cancelled September 1, 2026 price rise and the 30% tokenizer jump to plan for
Claude Sonnet 5 launched on June 30, 2026 at $2/$10, a price Anthropic made permanent on August 10, cancelling the September 1 rise to $3/$15. Its new tokenizer counts about 30% more tokens. The cost math and fixes.
Manu Shukla