What percent is A of B? (A / B) × 100 when B ≠ 0.
The script always computes (part ÷ whole) × 100 as long as whole ≠ 0 (NaN inputs error out). Values above 100% are allowed mathematically—interpretation is up to you.
This calculator uses plain decimal numbers. If a result looks wrong, check whether you used a comma instead of a dot (or vice versa) where the field expects one.