Simon Willison first-party · 2d ago · 2/5
Claude Token Counter, now with model comparisons ↗
Simon Willison enhanced his Claude Token Counter tool to enable side-by-side tokenization comparisons across Claude models, including the newly released Opus 4.7. Testing revealed Opus 4.7's updated tokenizer uses 1.46× more tokens for text than Opus 4.6, and 3× more for high-resolution images, despite identical pricing. The tool now supports all four current Claude models and demonstrates that Opus 4.7's token inflation could increase costs by roughly 40% for typical text inputs.
Opus 4.7 uses an updated tokenizer that improves how the model processes text. The tradeoff is that the same input can map to more tokens—roughly 1.0–1.35× depending on the content type.
Opus 4.7 uses the same pricing is Opus 4.6 - $5 per million input tokens and $25 per million output tokens - but this token inflation means we can expect it to be around 40% more expensive.