PHP 4, PHP 5, PHP 7, PHP 8
count_chars - Return information about characters used in a string

count_chars( string$string, [int$mode = 0] ): array|string

Counts the number of occurrences of every byte-value (0..255) in string and returns it in various ways.



The examined string.


See return values.

Return Values

Depending on mode count_chars returns one of the following:

0 - an array with the byte-value as key and the frequency of every byte as value.

1 - same as 0 but only byte-values with a frequency greater than zero are listed.

2 - same as 0 but only byte-values with a frequency equal to zero are listed.

3 - a string containing all unique characters is returned.

4 - a string containing all not used characters is returned.


Version Description
8.0.0 Prior to this version, the function returned false on failure.

Related Functions

Example of count_chars

Show all examples for count_chars

PHP Version:

Function count_chars:

Strings Functions

Most used PHP functions