Text & writing
Barcode check digit calculator
Generate or check EAN-8, UPC-A and EAN-13 arithmetic checksums.
A clear answer. Here’s how.
Starting at the rightmost body digit, alternates weights 3 and 1. The check digit is the amount needed to reach a multiple of 10. Requires exact format length and preserves leading zeros. This checks numeric composition only; it does not allocate a GS1 identifier, establish a product record or generate a barcode image.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- Number format
- EAN-13 / GTIN-13
- Operation
- Validate complete number
- Digits (omit final digit in generate mode)
- 4006381333931
Example result
- Check digit
- 1
- Complete number
- 4006381333931
- Supplied checksum
- Passes
GS1 modulo-10 alternating 3/1 weights from the right of the body. A passing checksum does not confirm GS1 allocation or product identity.