Function parseLocalizedNumber

parseLocalizedNumber(raw: string): number

Parses a numeric token that may use US or European grouping/decimal conventions into a number. When both . and , are present the last-occurring one is treated as the decimal separator and the other as thousands grouping; a single , or . is treated as a decimal point (so European 149,19 reads as 149.19); repeated separators of one kind are treated as grouping only.

Parameters

raw: string
The numeric token (e.g. "149,19", "1.234,56", "1,234.56", "40")

Returns number

The parsed number (may be NaN if the token holds no digits)

Example

parseLocalizedNumber("149,19")    // 149.19
parseLocalizedNumber("1.234,56")  // 1234.56
parseLocalizedNumber("1,234.56")  // 1234.56
parseLocalizedNumber("40")        // 40

Source

export const parseLocalizedNumber = (raw: string): number => {
  const commaCount = (raw.match(/,/g) ?? []).length;
  const dotCount = (raw.match(/\./g) ?? []).length;
  // Both separators present: the last-occurring one is the decimal, the other groups thousands.
  if (commaCount > 0 && dotCount > 0) {
    const decimal = raw.lastIndexOf(',') > raw.lastIndexOf('.') ? ',' : '.';
    const grouping = decimal === ',' ? /\./g : /,/g;
    return Number(raw.replace(grouping, '').replace(decimal, '.'));
  }
  // A single comma or single dot is a decimal separator (handles EU "149,19" and US "140.22").
  if (commaCount === 1) return Number(raw.replace(',', '.'));
  if (dotCount === 1) return Number(raw);
  // No separator, or repeated separators used purely for grouping (e.g. "1,234,567").
  return Number(raw.replace(/[.,]/g, ''));
};