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Function: formatNumber() ​

ts
function formatNumber(input: number, mask: string): string;

Defined in: format-number.ts:549

Formats a number according to the specified mask.

The mask can be a standard numeric format string (e.g., "C", "D", "E", "F", "G", "N", "P", "R", "X") with an optional precision specifier, or a custom numeric format string with optional sections for positive, negative, and zero values separated by semicolons.

Standard format specifiers:

  • "C" or "c": Currency format.
  • "D" or "d": Decimal format.
  • "E" or "e": Scientific (exponential) format.
  • "F" or "f": Fixed-point format.
  • "G" or "g": General format (compact representation).
  • "N" or "n": Number format with group separators.
  • "P" or "p": Percent format.
  • "R" or "r": Round-trip format (ensures that a number converted to a string and back again yields the same number).
  • "X" or "x": Hexadecimal format.

Custom format strings can include digit placeholders, group separators, decimal points, and optional sections for positive, negative, and zero values.

Parameters ​

ParameterTypeDescription
inputnumberThe number to format.
maskstringThe format mask string.

Returns ​

string

The formatted number as a string.

Example ​

typescript
formatNumber(1234.56, "C2"); // "$1,234.56"
formatNumber(-42, "D5");     // "-00042"
formatNumber(0.123, "P1");   // "12.3 %"
formatNumber(12345.678, "#,##0.00"); // "12,345.68"