# Posts Tagged EAN barcode

On one of the applications I am working on, I had to validate an EAN (European Article Number) barcode.
This application is mostly using JavaScript validation so I asked my friend Google to find me a JavaScript method which would check my EAN barcode.
It found validators in different languages but none in JavaScript. 🙁

Because one is never better served than by oneself, I decided to write it myself and share it with you. 😉

```function checkEan(eanCode) {
// Check if only digits
var ValidChars = "0123456789";
for (i = 0; i < eanCode.length; i++) {
digit = eanCode.charAt(i);
if (ValidChars.indexOf(digit) == -1) {
return false;
}
}

// Add five 0 if the code has only 8 digits
if (eanCode.length == 8 ) {
eanCode = "00000" + eanCode;
}
// Check for 13 digits otherwise
else if (eanCode.length != 13) {
return false;
}

// Get the check number
originalCheck = eanCode.substring(eanCode.length - 1);
eanCode = eanCode.substring(0, eanCode.length - 1);

even = Number(eanCode.charAt(1)) +
Number(eanCode.charAt(3)) +
Number(eanCode.charAt(5)) +
Number(eanCode.charAt(7)) +
Number(eanCode.charAt(9)) +
Number(eanCode.charAt(11));
// Multiply this result by 3
even *= 3;

odd = Number(eanCode.charAt(0)) +
Number(eanCode.charAt(2)) +
Number(eanCode.charAt(4)) +
Number(eanCode.charAt(6)) +
Number(eanCode.charAt(8)) +
Number(eanCode.charAt(10));

total = even + odd;

// Calculate the checksum
// Divide total by 10 and store the remainder
checksum = total % 10;
// If result is not 0 then take away 10
if (checksum != 0) {
checksum = 10 - checksum;
}

// Return the result
if (checksum != originalCheck) {
return false;
}

return true;
}
```

Note that this code can validate EAN-8 and EAN-13 barcodes.