(PHP 4, PHP 5)
base_convert — Convert a number between arbitrary bases
$number
    , int $frombase
    , int $tobase
    )
   Returns a string containing number
   represented in base tobase.  The base in
   which number is given is specified in
   frombase.  Both
   frombase and tobase
   have to be between 2 and 36, inclusive.  Digits in numbers with a
   base higher than 10 will be represented with the letters a-z,
   with a meaning 10, b meaning 11 and z meaning 35.
  
base_convert() may lose precision on large numbers due to properties related to the internal "double" or "float" type used. Please see the Floating point numbers section in the manual for more specific information and limitations.
numberThe number to convert
frombase
       The base number is in
      
tobase
       The base to convert number to
      
   number converted to base tobase
  
Example #1 base_convert() example
<?php
$hexadecimal = 'A37334';
echo base_convert($hexadecimal, 16, 2);
?>
The above example will output:
101000110111001100110100