Variable handling Functions
PHP Manual

is_numeric

(PHP 4, PHP 5, PHP 7)

is_numeric Finds whether a variable is a number or a numeric string

Description

bool is_numeric ( mixed $var )

Finds whether the given variable is numeric. Numeric strings consist of optional sign, any number of digits, optional decimal part and optional exponential part. Thus +0123.45e6 is a valid numeric value. Hexadecimal (e.g. 0xf4c3b00c) and binary (e.g. 0b10100111001) notation is not allowed.

Parameters

var

The variable being evaluated.

Return Values

Returns TRUE if var is a number or a numeric string, FALSE otherwise.

Examples

Example #1 is_numeric() examples

<?php
$tests 
= array(
    
"42",
    
1337,
    
0x539,
    
02471,
    
0b10100111001,
    
1337e0,
    
"not numeric",
    array(),
    
9.1,
    
null
);

foreach (
$tests as $element) {
    if (
is_numeric($element)) {
        echo 
var_export($elementtrue) . " is numeric"PHP_EOL;
    } else {
        echo 
var_export($elementtrue) . " is NOT numeric"PHP_EOL;
    }
}
?>

The above example will output:

'42' is numeric
1337 is numeric
1337 is numeric
1337 is numeric
1337 is numeric
1337 is numeric
'not numeric' is NOT numeric
array () is NOT numeric
9.0999999999999996447286321199499070644378662109375 is numeric
NULL is NOT numeric

Changelog

Version Description
7.0.0 Strings in hexadecimal (e.g. 0xf4c3b00c) notation are no longer regarded as numeric strings, i.e. is_numeric() returns FALSE now.

See Also


Variable handling Functions
PHP Manual