PHP: Converting A String To Integer

The intval() variable handling function can be used to convert a string to a integer value. A base parameter for the conversion is optional.

Syntax

With optional base parameter:

$integer = intval($any_variable, $base);

Without optional base parameter:

$integer = intval($any_variable);

$integer

The returned integer value on successful conversion, or 0 on failure. Empty arrays will return 0 and non-empty arrays will return 1. See examples below.

$any_variable (var parameter)

Required parameter that accepts multiple data types. It is the scalar value being converted to an integer.

$base (base parameter)

Optional parameter as integer data type. It is the base for the conversion. Default base is 10 and has no effect unless the var parameter is a string. See examples below.

Examples

String Conversion

Without optional base parameter:

$integer = intval($any_variable);

With optional base parameter:

$integer = intval($any_variable, $base);

¹⁾ Unsuccessful conversion as 37 is not a valid binary number.

Number Conversion

Without optional base parameter:

$integer = intval($any_variable);

¹⁾ Value for $any_variable precedes with 0 indicating octal (base 8) notation.
²⁾ Value for $any_variable precedes with 0x indicating hexadecimal (base 16) notation.

With optional base parameter:

$integer = intval($any_variable, $base);

¹⁾ The base parameter has no effect as the var parameter is not a string.

Array Conversion

Without optional base parameter:

$integer = intval($any_variable);