Claude Sonnet 5 opens at $2 per million tokens

Anthropic launched Claude Sonnet 5 at an introductory $2 per million input tokens and $10 per million output tokens, with both rates rising 50% after August 31 to $3 and $15. The Claude Sonnet 5 announcement says the model is now the default on Free and Pro plans, while its updated tokenizer can turn the same input into roughly 1.0–1.35 times as many tokens depending on the content. For teams comparing it with Claude Opus 5’s frontier-coding economics, benchmark cost per completed workflow before September rather than trusting the temporary list price.