The Same TypeScript Costs 73% More Tokens on Claude Than GPT

Playcode analysis: Anthropic’s newest tokenizer (Sonnet 5, Opus 4.8, Fable 5) produces ~30% more tokens from the same code than prior Anthropic tokenizer; up to 1.73x vs GPT-5.x on TypeScript. Sonnet 5 intro pricing $2/$10 through Aug 31, 2026 then $3/$15. Normalized to GPT-5.x baseline, Opus 4.8 effective cost ~$7.50/$37.50 vs list $5/$25. Anthropic acknowledges roughly 1.0–1.35× more tokens depending on content type.