Free UPC Barcode Generator

Who needs a UPC barcode

A UPC is the barcode that checkout scanners in the United States and Canada expect on anything sold in a store. Its full name is Universal Product Code, and the number inside it is a GTIN-12, a global trade item number of twelve digits that points to one specific product from one specific company. When the cashier scans it, the register looks that number up in the store's own system to find the name and the price. Online marketplaces use the same numbers to match listings to products, which is why many of them ask for a UPC before you can list an item.

Outside North America the same job is done by the EAN-13, and the two are closer than they look. A UPC-A is an EAN-13 with a zero in front, and scanners everywhere read both, so a product with a UPC can be sold in Europe and a product with an EAN-13 from a European GS1 office can usually go on an American shelf as it is. You only need to pick UPC deliberately when a retailer, a distributor or a marketplace asks for it by name, and in the United States that still happens often.

If the barcode is only for your own stockroom, shelves or equipment, you don't need a UPC at all. Internal codes such as SKUs, bin locations or asset numbers belong in a Code 128 barcode, which also takes letters. The barcode generator explains which type suits which job.

Getting a UPC number from GS1

This page draws any valid UPC you give it, but the number itself has to come from GS1, the organization that manages product numbers worldwide. In the United States that is GS1 US, which licenses either a company prefix, a block of digits that becomes the start of all your product numbers, or single numbers for a business with only a handful of products. Canadian businesses get theirs from GS1 Canada. Either way, your company is recorded as the owner of those numbers, and that record is what retailers and marketplaces check when you list a new product.

That check is also why cheap UPCs bought from resellers so often end in a rejected listing. Many of those numbers were licensed to another company years ago and passed on, so the registry still names that company, or nobody, as the brand owner. The barcode scans perfectly, but the number behind it doesn't lead back to your business. Once you have numbers of your own, keep a simple list of which number went to which product, so that none is ever given out twice.

What the 12 digits mean

A UPC-A has twelve digits in three parts, even though the barcode doesn't show where one ends and the next begins. The first part is your GS1 company prefix, the second is the item reference you choose for each product, and the last digit is a check digit calculated from the other eleven. The company prefix has no fixed length: a business that licensed room for many products gets a shorter prefix and more digits for its items, while one that licensed only a few gets a longer prefix and fewer item digits, so you can't tell from the digits alone where the prefix ends. GS1 US usually shows your GS1 Company Prefix with a 0 in front; the U.P.C. company prefix at the start of a UPC-A is the same number without that 0.

The first digit used to be called the number system digit, and it still means something in a few cases. Numbers that begin with 2 are kept for stores to use inside their own walls, for example on the labels a supermarket prints for meat or cheese sold by weight, so a UPC you license from GS1 won't start with a 2. On the printed barcode, the first and last digits stand smaller outside the bars, and the ten in between sit underneath in two groups of five.

The generator handles the check digit for you, and the check digit calculator does the same for a single number or a whole list without making a barcode. Type eleven digits and it adds the twelfth and shows which one it added; type all twelve and it compares the last one with the calculation and offers Fix it when they differ. For a number GS1 assigned to you, a difference nearly always means a typo, so look the number up in your GS1 account rather than simply clicking the fix.

UPC-A or UPC-E

UPC-E is a shortened form of UPC-A for packs too small for the full barcode, such as a lip balm or a small bottle. It prints only eight digits and is a little more than half as wide, about 22 mm instead of about 37 mm at the standard size including the quiet zones. It isn't a different number, though: a UPC-E is a UPC-A with a run of zeros left out, and the scanner puts the zeros back and reports all twelve digits to the register. Only UPC-A numbers that start with 0 and have four or five zeros in the right places can be shortened this way.

An example shows how it works. The UPC-E 04252614 stands for the UPC-A 042100005264: the scanner restores the four zeros after 0421 and reads the code as that full number, with the same check digit at the end. With UPC-E selected you can type the six middle digits or seven digits, and the generator adds the check digit and shows the UPC-A the code stands for, so you can compare it with the number GS1 gave you; type all eight and it checks the last digit instead.

So you can't simply decide to use UPC-E. Whether a product number can be shortened depends on the number itself, most numbers can't, and the generator won't shorten a UPC-A for you. If a pack has no room for a UPC-A even at the smallest retail size, ask GS1 which of your numbers can be printed as UPC-E before you design the packaging around one.

Printing a UPC that scans at the checkout

A UPC has a standard size, called 100 %, at which it is about 37 mm (roughly 1.5 inches) wide including the quiet zones of nine modules on each side, and stores accept anything from 80 % to 200 % of that. At 80 % it is about 30 mm (1.2 inches) wide, the smallest the retail rules allow, which is why the size menu here stops there. When you choose a printer, the bars snap to whole printer dots and the page shows the percentage that results; it rounds up rather than down whenever the nearest dot would fall below 80 %, so the smallest UPC is about 114 % on a 203 dpi thermal printer and about 103 % on a 300 dpi printer. Keep the bars at their full height as well, because a UPC cut short to fit a narrow label is harder to read at an angle and is one of the things retailers' barcode checks flag.

Checkout scanners read with red light, so color matters more than it seems. Black bars on white are always safe, and dark blue or dark green bars usually work, but red, orange and yellow bars reflect red light just like the background and disappear. The scan check warns when the bars are lighter than the background, but it can't see your packaging, so a printed proof scanned with a real scanner is the final test.

Where the barcode sits matters too. Put it on a flat area, away from folds, seams and the edges of the pack, and on a narrow bottle turn it so that it reads along the straight height of the container rather than around its curve. If your products don't have the barcode printed on the packaging, a sticker does the same job: Print on labels opens the editor with the UPC at the size you chose, for example on a 2¼×1¼″ thermal label, and the page on barcode labels covers sticker sheets and label printers.