Barcode Check Digit Calculator
Validate a barcode online for free: the tool recalculates the EAN-13, EAN-8 or UPC-A check digit, shows the code format and the GS1 country prefix. No sign-up, works with any packaging.
The first three digits identify the country where the manufacturer registered the code. Just enter the full code from the packaging — spaces and dashes are fine.
Examples:
How the barcode check works
Enter every digit from the packaging — usually 13 (EAN-13), sometimes 8 (EAN-8) or 12 (UPC-A, used in the USA and Canada). The tool recalculates the check digit: the last digit of any GTIN is mathematically derived from the others (alternating 1× and 3× weights, rounded up to the nearest ten). If it doesn't match, the code was mistyped or made up. You also get the GS1 country prefix.
An honest note about the limits: a valid check digit proves the code is well-formed, not that the product is genuine — a real product's code can be copied onto a fake. A failing check digit, however, is a reliable sign of a fabricated code. For real authentication use the manufacturer's own verification service where available.
Barcode check FAQ
How do I calculate an EAN-13 check digit?
Take the first 12 digits, multiply them alternately by 1 and 3 starting from the left, add everything up, and subtract the sum's last digit from 10 (10 → 0). The tool above does this instantly for EAN-13, EAN-8, UPC-A and GTIN-14.
Can a barcode tell me if a product is genuine?
Only partially. A failing check digit proves the code is fake. A passing one proves the code exists mathematically — but genuine codes can be copied, so it is not proof of authenticity.
Can I look up the product name by barcode?
The code itself only encodes the GS1 prefix and the company number. Product names live in third-party databases of varying completeness — there is no single official public registry.
What formats does the calculator support?
EAN-13 (13 digits, worldwide retail), EAN-8 (8 digits, small packages), UPC-A (12 digits, USA and Canada) and GTIN-14 (logistics). The format is detected automatically from the length.