Claude Opus 4.7's new tokenizer uses 1.47x more tokens than 4.6 on technical docs—higher than Anthropic's 1.35x claim; same price, faster quota burn, hits code harder than prose.

I Measured Claude 4.7's New Tokenizer. Here's What It Costs You.

Anthropic's Claude Opus 4.7 migration guide says the new tokenizer uses "roughly 1.0 to 1.35x as many tokens" as 4.6. I measured 1.47x on technical docs. 1.45x on a real CLAUDE.md file. The top of Anthropic's range is where most Claude Code content actually sits, not the middle.Same sticker price. Same quota. More tokens per prompt. Your Max window burns through faster. Your cached prefix costs more per turn. Your rate limit hits sooner.So Anthropic must be trading this for something. What? And ...