(PHP 4, PHP 5, PHP 7, PHP 8)
strnatcasecmp — Case insensitive string comparisons using a "natural order" algorithm
strnatcasecmp(string $string1, string $string2): int
This function implements a comparison algorithm that orders alphanumeric strings in the way a human being would. The behaviour of this function is similar to strnatcmp(), except that the comparison is not case sensitive. For more information see: Martin Pool's » Natural Order String Comparison page.
string1The first string.
string2The second string.
Returns a value less than 0 if string1 is less than string2; a value greater than 0 if string1 is greater than string2, and 0 if they are equal. No particular meaning can be reliably inferred from the value aside from its sign.
| Version | Description |
|---|---|
| 8.2.0 | This function is no longer guaranteed to return strlen($string1) - strlen($string2) when string lengths are not equal, but may now return -1 or 1 instead. |
Example #1 strnatcasecmp() example
<?php
var_dump(strnatcasecmp('Apple', 'Banana'));
var_dump(strnatcasecmp('Banana', 'Apple'));
var_dump(strnatcasecmp('apple', 'Apple'));
?> The above example will output:
int(-1) int(1) int(0)
© 1997–2025 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.strnatcasecmp.php