Number

A number is either a float or an integer.

Numbers are always signed. They are limited, in range, by the constants PHP_INT_MAX, PHP_INT_MIN, and PHP_FLOAT_MAX, PHP_FLOAT_MIN.

PHP also has a concept of numeric strings, which are strings that hold numbers. Other types do not have direct conversion to numbers and need to be converted or cast.

<?php

    echo 1;
    echo -1.5;

    echo PHP_INT_MAX;

?>

Documentation

See also PHP Numbers Basics, PHP Numbers Explained and Exploring Number Manipulation in PHP.

Related : Floating Point Numbers, integer, Numeric String, Cast Operator, abs()