UPC barcode generator for products sold in the US and Canada

A UPC-A barcode is the standard 12-digit retail barcode in the United States and Canada. UPC stands for Universal Product Code. The number it holds is a GTIN-12 (Global Trade Item Number), issued through GS1 US, and it identifies one specific product variant at the checkout and in the supply chain.

UPC barcodes were first scanned at a US supermarket checkout in 1974, and UPC-A remains the most familiar barcode on North American packaging.

What the 12 digits mean

• GS1 Company Prefix: assigned to your business by GS1 US. Its length varies with how many products you need to number.
• Item reference: the digits you assign to each product, size and pack.
• Check digit: the final digit, calculated from the first 11.

How the bars are laid out

A UPC-A barcode is 95 modules wide: a start guard, six left-hand digits, a center guard, six right-hand digits and an end guard. Each digit uses 7 modules made of two bars and two spaces.

UPC-A and EAN-13

A UPC-A number is a 12-digit GTIN. Add a leading 0 and you get the equivalent 13-digit EAN-13 number. Scanners in North America read both formats, so products with an EAN-13 barcode can also be sold there.

You get a UPC number from GS1 US, the organization that administers UPC numbering in the United States. CardDeck generates the barcode image from your number; it does not issue numbers.

Options from GS1 US

1. A GS1 Company Prefix: a block of numbers for brands with several products. You assign item references within the block.
2. Individual GTINs: a single number for a business with one or a few products, where GS1 US offers this.

In Canada, numbers come from GS1 Canada. Elsewhere, contact your local GS1 member organization, which issues numbers you can use as EAN-13 or, if they start with 0, as UPC-A.

Avoid resold numbers

Numbers sold cheaply by third parties were often licensed to a different company. Retailers and marketplaces can check the number against GS1 records, and a mismatch can lead to rejected listings.

Every variant needs its own number

Each size, flavor, color and pack size is a separate product with its own GTIN. A six-pack and a single can need different numbers. Keep a simple product list with each GTIN, description and pack size, and generate barcodes from that list so the number on the pack always matches your records.

The UPC-A check digit uses the GS1 modulo-10 method: multiply the digits in odd positions by 3 and the digits in even positions by 1, add everything, and find the number that brings the total up to the next multiple of 10.

Worked example: 03600029145

1. Odd positions (1st, 3rd, 5th, 7th, 9th, 11th): 0, 6, 0, 2, 1, 5. Their sum is 14. Multiply by 3: 42.
2. Even positions (2nd, 4th, 6th, 8th, 10th): 3, 0, 0, 9, 4. Their sum is 16.
3. Add: 42 + 16 = 58.
4. The next multiple of 10 is 60. 60 − 58 = 2.
5. The check digit is 2, so the full UPC-A is 036000291452.

If the total is already a multiple of 10, the check digit is 0.

What CardDeck does

• Enter 11 digits and CardDeck adds the check digit.
• Enter 12 digits and CardDeck verifies the last one. A mismatch usually means a typo in the number.

The method is the same as EAN-13; only the starting weight differs, because EAN-13 has one more digit at the front.

At 100% magnification, a UPC-A barcode is about 37.3 mm (1.47 in) wide and 25.9 mm (1.02 in) tall including quiet zones, with an X-dimension of 0.33 mm. GS1 allows 80% to 200% magnification for general retail.

Quiet zones

Leave at least 9 times the X-dimension clear on each side, about 3 mm at 100%. Do not let text, borders, folds or the edge of a label run into this space.

Height

Keep the full bar height. Shortening the bars to fit a small pack makes the barcode harder to scan at a checkout, and GS1 discourages it. If your pack is genuinely small, ask GS1 US about UPC-E, a compressed format for small packages.

Printing tips

• Black bars on a white background are safest.
• Never use red bars; checkout scanners use red light.
• Use SVG so bars stay sharp at any magnification.
• Print a proof on the real material and scan it before the full run.
• Put the barcode on a flat area, away from seams and tight curves.
• Ask your printer whether the printing process needs a minimum magnification above 80%.

Choose UPC-A, enter the first 11 digits of your GTIN-12, check the preview and download an SVG for your packaging. For a full range, generate them from a spreadsheet.

Single barcode

1. Open the barcode generator and choose UPC-A.
2. Enter 11 digits, or all 12 to verify an existing check digit.
3. Confirm the digits under the bars match your product record.
4. Download SVG and place it in your packaging artwork at 80–200% of nominal size.
5. Test-scan a printed proof.

A whole product range

1. Put each GTIN in its own spreadsheet row and format the column as Text, so Excel keeps the leading 0.
2. Upload the file to the bulk barcode generator and choose UPC-A.
3. Fix flagged rows, such as numbers with 10 digits or wrong check digits.
4. Download a ZIP of SVG files, one per product.

For stock control and shelf labels alongside retail barcodes, see CardDeck for retail and inventory.

Before you send artwork to print

1. Check the number against your GS1 US record.
2. Confirm the barcode is at least 80% of nominal size.
3. Confirm quiet zones are clear on both sides.