Anthropic itself notes in its migration guide that token usage may rise by roughly 1.0x to 1.35x. Ray’s measurements on real Claude Code content show an average increase of 1.325x, rising to 1.445x for a CLAUDE.md file and 1.47x for technical documentation. A community analysis on tokens.billchambers.me, based on 483 submissions, reports an even larger increase: 37.4 percent more tokens and cost per request.
According to Ray, code-heavy workloads are affected more than prose, while Chinese and Japanese texts show little change. For a sample session with 80 rounds, he estimates additional costs of roughly 20 to 30 percent, increasing from $6.65 to about $7.86 to $8.76. In return, a test using the IFEval benchmark with 20 prompts showed an improvement of about five percentage points in following strict instructions.
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