How to add a thousands Separator in PHP

1. Add a string function:

Number_format (number, decimals, decimalpoint, separator)
Parameters	Description
Number	Required. The number to be formatted. If no other parameter is set, the number is formatted as a comma (,) without a decimal point.
Decimals	Optional. Specifies the number of decimal places. If this parameter is set, the period (.) is used as the decimal point to format the number.
Decimalpoint	Optional. Specifies the string used as the decimal point.
Separator	Optional. A string that is required to be used as a thousands separator. Use only the first character of this parameter. For example, "xyz" only outputs "x ". Note: If this parameter is set, all other parameters are required.
Example	<? Php Echo number_format ("1000000 "); Echo number_format ("1000000", 2 ); Echo number_format ("1000000", 2 ,",","."); ?> Output: 1,000,000 1,000,000.00 1.000.000, 00

2. Regular Expression:

Echo preg_replace ('/(? <= [0-9]) (? = (? : [0-9] {3}) + (?! [0-9])/', 5245201526.52 );