Format Number - Hhvm

:::info[Note] This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information. :::

Returns a string representation of the given number with grouped thousands

Hack

namespace HH\Lib\Str;

function format_number(
  num $number,
  int $decimals = 0,
  string $decimal_point = '.',
  string $thousands_separator = ',',
): string;

If $decimals is provided, the string will contain that many decimal places. The optional $decimal_point and $thousands_separator arguments define the strings used for decimals and commas, respectively.

Guide

String

Parameters

num $number
int $decimals = 0
string $decimal_point = '.'
string $thousands_separator = ','

Returns

string