PHP | str_rot13() Function

The function str_rot13() is a built-in function in php. This function accepts a string and shifts every alphabet present in the string by 13 places in the alphabet. The function leaves numeric and non-alphabetical characters untouched. By passing an encoded string as argument, the function will return the original string.


str_rot13 ( $string )

Parameter: This function accepts only a string parameter which can be observed from the above syntax. The description of the parameter is as follows.

  • $string : This is the only mandatory parameter of the function. This parameter passes a string to the function which needs to be encoded.

Return Value: The function returns the encoded string.


Input : $string = "Geeks for Geeks"
Output : Trrxf sbe Trrxf

Input : $string = "Trrxf sbe Trrxf"
Output : Geeks for Geeks

Below program illustrate the str_rot13() function in PHP:





echo str_rot13("Geeks for Geeks");
echo "\n";
echo str_rot13("Trrxf sbe Trrxf");



Trrxf sbe Trrxf
Geeks for Geeks


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