The is_numeric Function

The is_numeric function checks whether the passed value is a number or a string that can be interpreted as a number. The function returns true if the value is a number or a numeric string, and false otherwise.

Syntax

phpis_numeric(mixed $value): bool

Example

Let's check several values for compliance with the numeric format:

php<?php
  var_dump(is_numeric(123));      // true
  var_dump(is_numeric('123'));    // true
  var_dump(is_numeric('12.3'));   // true
  var_dump(is_numeric('abc'));    // false
  var_dump(is_numeric('123a'));   // false
?>

Example

Let's check the operation with various numeric formats:

php<?php
  var_dump(is_numeric(0x1A));      // true (hexadecimal)
  var_dump(is_numeric('0x1A'));    // false (string with hexadecimal number)
  var_dump(is_numeric(1.2e3));     // true (exponential notation)
  var_dump(is_numeric('1.2e3'));   // true (string with exponential notation)
?>

See Also