Including the existing check digit as data
Supplying all digits to calculation mode shifts the weighting and produces a misleading result.
Use calculation mode for the data-only length or verification mode for the complete identifier.
barcode check digit calculator
Calculate a barcode check digit and see the math
Enter the data digits for a supported format and BatchLabel applies the correct alternating weights, modulus and final subtraction. The result includes the completed number and an explanation you can use to audit a spreadsheet formula.
Modulo-10 check digitLeading zeroes are kept as text.
EAN-13 accepts 12 digits before the check digit or 13 including it.
Calculated check digit
14006381333931Append 1 to obtain the complete EAN-13 value.A practical workflow
How to use it
- 01
Choose the target format
Select EAN-13, EAN-8, UPC-A or ITF-14 so the expected data length is explicit.
- 02
Enter data digits
Paste the digits before the check digit, preserving any leading zero.
- 03
Verify the completed value
Copy the result back to the source system and validate it there before generating artwork.
Avoid rework
Common errors and precise fixes
Dropping a leading zero
Weights depend on position, so a removed zero changes both length and checksum.
Treat the value as text and enter every data position.
Know the limits
The calculator covers the check-digit algorithms explicitly listed, not arbitrary barcode formats.
It does not reserve, register or look up identifiers.
Questions, answered
Before you continue
Why does a check digit sometimes equal zero?
When the weighted sum is already divisible by ten, the amount needed to reach the next multiple of ten is zero.
Does a correct check digit make the number official?
No. It only detects many typing errors. Assignment and permitted use are separate questions handled by the relevant issuing body.