### works

# PHP Validate UPC and EAN13 Barcodes

### As I couldn't find any routines to do this...

I hacked these up in Perl an age ago... needed PHP versions so here they are (Ask if you want the Perl versions lazy..)

function validate_UPCABarcode($barcode)

{

// check to see if barcode is 12 digits long

if(!preg_match("/^[0-9]{12}$/",$barcode)) {

return false;

}

$digits = $barcode;

// 1. sum each of the odd numbered digits

$odd_sum = $digits[0] + $digits[2] + $digits[4] + $digits[6] + $digits[8] + $digits[10];

// 2. multiply result by three

$odd_sum_three = $odd_sum * 3;

// 3. add the result to the sum of each of the even numbered digits

$even_sum = $digits[1] + $digits[3] + $digits[5] + $digits[7] + $digits[9];

$total_sum = $odd_sum_three + $even_sum;

// 4. subtract the result from the next highest power of 10

$next_ten = (ceil($total_sum/10))*10;

$check_digit = $next_ten - $total_sum;// if the check digit and the last digit of the barcode are OK return true;

if($check_digit == $digits[11]) {

return true;

}

return false;

}function validate_EAN13Barcode($barcode)

{

// check to see if barcode is 13 digits long

if(!preg_match("/^[0-9]{13}$/",$barcode)) {

return false;

}$digits = $barcode;

// 1. Add the values of the digits in the even-numbered positions: 2, 4, 6, etc.

$even_sum = $digits[1] + $digits[3] + $digits[5] + $digits[7] + $digits[9] + $digits[11];

// 2. Multiply this result by 3.

$even_sum_three = $even_sum * 3;

// 3. Add the values of the digits in the odd-numbered positions: 1, 3, 5, etc.

$odd_sum = $digits[0] + $digits[2] + $digits[4] + $digits[6] + $digits[8] + $digits[10];

// 4. Sum the results of steps 2 and 3.

$total_sum = $even_sum_three + $odd_sum;

// 5. The check character is the smallest number which, when added to the result in step 4, produces a multiple of 10.

$next_ten = (ceil($total_sum/10))*10;

$check_digit = $next_ten - $total_sum;// if the check digit and the last digit of the barcode are OK return true;

if($check_digit == $digits[12]) {

return true;

}return false;

}