Simon Willison / Simon Willison's Weblog:Anthropic prices Claude Sonnet 4.5 at $3/1M input and $15/1M output tokens, same as Sonnet 4, cheaper than Opus at $15/$75 but higher than GPT-5 at $1.25/$10 — Anthropic released Claude Sonnet 4.5 today, with a very bold set of claims: … Anthropic gave me access to a preview version of a …