Same Number, Two Ways
Today Hacker News carried The Hustle's "Why barcodes are about to go extinct". Under GS1's plan, called Sunrise 2027, the stripes on a pack get a square partner: a QR code that carries the same product number and more. Here are both, built from a number you can edit, and the article's dates checked.
The default is the number in Wikipedia's UPC-A illustration, 036000291452. I checked this page's bar pattern against that image module by module: all 95 match. The QR holds the same number written as a GS1 Digital Link, a web address with the 14-digit GTIN after /01/, the batch after /10/ and the expiry as ?17=. The stripes have no room for the batch or the date. The QR is drawn by the qrcode-generator library.
What the twelfth digit catches
The check digit is chosen so that three times the sum of the odd-place digits, plus the even-place digits, plus the check digit, ends in 0. Change any one digit and the total no longer ends in 0, so the scanner refuses it. Swap two neighbours and the total moves by twice their difference. That is a multiple of ten only when the two differ by exactly 5.
So 0↔5, 1↔6, 2↔7, 3↔8 and 4↔9 swaps get through: 10 of the 90 ordered pairs of different digits, one in nine.
The article's dates
| The Hustle | Source | |
|---|---|---|
| First scan: 1974, Troy, Ohio, a pack of Juicy Fruit | Wikipedia, Universal Product Code: a 10-pack of Wrigley's Juicy Fruit at the Marsh supermarket, 8:01 a.m., 26 June 1974; the register rang up 67 cents | matches |
| QR code by Masahiro Hara at Denso, inspired by Go | Wikipedia, QR code: invented in 1994 by Hara's team at Denso Wave; the first design took after the black and white stones on a Go board | matches |
| "Two years ago, though, GS1 made an announcement. The barcode was out." | GS1 US's page "Get Ready for Sunrise 2027" was already up when the Internet Archive saved it on 3 October 2022, and Wikipedia's GS1 dates the launch to 2022. That is four years before the article. | earlier |
| Photo caption: "Food recalls, like the one on infant formula in 2021" | Wikipedia, 2022 United States infant formula shortage: Abbott's recall and the Sturgis plant shutdown came in February 2022 | 2022 |
| "The barcode was out" | GS1 US's own 2022 page talks of point-of-sale scanners learning to accept 2D codes. The article itself says packs must carry both codes until retail catches up. | softer |
What stands on what
| Item | Source |
|---|---|
| Bar patterns, guard bars, 95 modules | Wikipedia, Universal Product Code, and its illustration UPC-A-036000291452.svg, compared module by module |
| Digital Link syntax | GS1, GS1 Digital Link: URI Syntax (ref.gs1.org), examples such as https://id.gs1.org/01/09520123456788/10/ABC1/21/12345?17=180426 |
| Sunrise 2027 in 2022 | GS1 US, "Get Ready for Sunrise 2027", Internet Archive capture of 3 October 2022; Wikipedia, GS1 |
| The article | Katherine Laidlaw, "Why barcodes are about to go extinct", The Hustle, 1 October 2026 |
| Check-digit blind spot | My arithmetic, confirmed by running every pair in the page's script |