Complete twelve-digit product identifiers.
Initialising algorithm engine for GTIN-12 / UPC-A Calculator...
How GTIN-12 / UPC-A Calculator Works?
The GTIN-12 / UPC-A Calculator works by multiplying the 6 odd-position digits by 3, adding the 5 even-position digits, and appending the digit that brings the total to a multiple of 10.
- 1Enter the 11-digit payload (number system digit, company prefix, and item reference).
- 2Add the digits in positions 1, 3, 5, 7, 9, and 11 and multiply the result by 3.
- 3Add the digits in positions 2, 4, 6, 8, and 10.
- 4Add both results to get S.
- 5Compute the 12th digit as (10 − (S mod 10)) mod 10.
GTIN-12 / UPC-A Calculator Formula
The UPC-A formula is d₁₂ = (10 − ((3 × odd-position sum + even-position sum) mod 10)) mod 10.
S = 3 × (d₁ + d₃ + d₅ + d₇ + d₉ + d₁₁) + (d₂ + d₄ + d₆ + d₈ + d₁₀) d₁₂ = (10 − (S mod 10)) mod 10
d₁…d₁₁are the payload digits from the left.d₁₂is the UPC-A check digit.
Payload: 03600029145 Weights: 31313131313 S = 58 Check digit = (10 − (58 mod 10)) mod 10 = 2 UPC-A = 036000291452
GTIN-12 / UPC-A Calculator Conversion Table
The GTIN-12 conversion table maps 11-digit payloads to complete UPC-A codes and their EAN-13 equivalents.
| Payload (11 digits) | Check digit | UPC-A | EAN-13 equivalent | GTIN-14 format |
|---|---|---|---|---|
| 03600029145 | 2 | 036000291452 | 0036000291452 | 00036000291452 |
| 01234567890 | 5 | 012345678905 | 0012345678905 | 00012345678905 |
| 04210000526 | 4 | 042100005264 | 0042100005264 | 00042100005264 |
| 07447011141 | 2 | 074470111412 | 0074470111412 | 00074470111412 |
| 88543204502 | 3 | 885432045023 | 0885432045023 | 00885432045023 |
| 19202702001 | 4 | 192027020014 | 0192027020014 | 00192027020014 |
What is GTIN-12 / UPC-A Calculator?
A GTIN-12 / UPC-A Calculator is a tool that computes the 12th digit of a Universal Product Code (UPC-A). UPC-A is the standard retail barcode in the United States and Canada.
A UPC-A becomes a valid EAN-13 by adding a leading zero, and the check digit stays the same. The first digit of a UPC-A is the number system digit: 0, 1, 6, 7, 8 for regular items, 2 for variable-weight items, 3 for drugs, and 5 for coupons.
What are the uses of GTIN-12 / UPC-A Calculator?
There are 4 main uses of the GTIN-12 / UPC-A Calculator, including US retail packaging, EAN conversion, and point-of-sale testing.
- US and Canadian retail packaging: Manufacturers complete UPC-A codes before printing labels.
- EAN-13 conversion: Exporters prefix a 0 to sell UPC-labelled goods in EAN markets.
- Point-of-sale testing: Retail IT teams create valid test UPCs for scanner trials.
- Catalogue validation: Distributors flag invalid UPCs in product feeds.