Numeric Base

The numeric base is the number of digits to be used when counting. The most common bases are: binary (0, 1), octal (0 to 7), decimal (0 to 9), duodecimal (0 to 11), hexadecimal (0 to F, aka 15).

All other bases, starting from 2, are possible.

In computer science, base 2, 10 and 16 are quite common, and require conversion from one another.

<?php

    $number = '1234';
    echo base_convert($number, 10, 8);  // 2322
    echo base_convert($number, 10, 12); // 86a
    echo base_convert($number, 10, 16); // 4d2

?>

Documentation

See also How to interact with Number Systems and Encoding Schemes in PHP.

Related : integer, Base, Leading Zero Means Octal