Calculated in your browser; your inputs are not sent to us. Privacy
Results update when you run the tool.
This tool processes the selected input in your browser. Review the output before relying on it; format and file behavior can vary by browser and source data.
Your inputs and results stay in this browser. This page may send privacy-bounded aggregate interaction events described in Privacy; it does not send your entered values or result contents.
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How This Tool Works
Calculation Method
EU size = US size + 10, applied to whole-number sizes from 20 to 60. Values outside that range are rejected as an invalid size rather than converted, since the +10 mapping is not defined for them.
Site methodology
No unrelated authority link is added merely to make this page look sourced. Tool-specific external sources are shown only when they directly support the method, rate, or rule.
Assumptions to Verify
- Inputs are treated exactly as entered.
- Verify important decisions with current authoritative information.
Privacy: The calculation runs in this browser. Shared links contain the page address only, not your inputs or results.