README

Luhn algorithm implementation for PHP. The Luhn algorithm is used in credit card numbers and national identity numbers.

Installation

To add this package as a dependency to your project, simply add a dependency on komakino/luhn to your project's composer.json file.

    {
        "require": {
            "komakino/luhn": "*"
        }
    }

use Komakino\Luhn\Luhn;

static bool validate(string|int $number)

Validates a number.

Luhn::validate('12345678'); // returns false
Luhn::validate('87654323'); // returns true

static int calculate(string|int $partial_number)

Calculates the check digit of a number.

Luhn::calculate('1234567'); // returns 4
Luhn::calculate('8765432'); // returns 3

static string appendCheckDigit(string|int $partial_number)

Calculates the check digit and returns number with check digit appended.

Luhn::appendCheckDigit('1234567'); // returns 12345674
Luhn::appendCheckDigit('8765432'); // returns 87654323