Annual gross salary divided by 12—rough monthly before tax.
Monthly pay is annual ÷ 12 (two decimals). The line labeled weekly uses annual ÷ 52 as a simple “weeks per year” approximation; it is not tied to your employer’s pay calendar.
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.