Does Shopify generate barcodes automatically?

No. Shopify gives each variant an empty Barcode field. You enter codes yourself, import them, or use an app such as SGT to generate them.

Can two variants share a barcode?

Shopify allows it, but scanners and Shopify POS then cannot tell the variants apart. Give every variant its own code. SGT's duplicate finder lists any that are shared.

How to add barcodes to Shopify products

Where the barcode lives in Shopify

Shopify stores one barcode per variant, in the Barcode (ISBN, UPC, GTIN, etc.) field on the variant page. A product with five sizes has five barcode fields. Shopify does not check whether the number is valid or unique, so it is easy to end up with typos or the same code on two variants.

Option 1: type them in by hand

In Shopify admin, open Products and choose a product.
Open a variant, or the single variant of a product without options.
Under Inventory, enter the code in Barcode and save.

This works for a handful of products. For a catalog it is slow, and one wrong digit means a label that scans as a different product.

Option 2: import codes from a spreadsheet

If you already bought codes and keep them in a spreadsheet, export your products from Shopify, fill the barcode column (called Variant Barcodes in recent exports) and import the file again. Keep the variant rows exactly as exported, or Shopify may create new variants. SGT can also import a CSV of codes and match each row to its variant by product handle and option values, or by variant ID.

Option 3: generate them in bulk

With SGT you enter your GS1 company prefix once. The app then builds a valid code with the correct check digit for every variant you select, skips any number your store already uses, and writes them straight to Shopify.

Install SGT and open Manual Generation.
Choose Barcode and your format: UPC-A, EAN-13, EAN-8 or ITF-14.
Enter your company prefix. SGT shows how many codes it has left.
Select products, a collection or the whole store, check the preview, and generate.

Turn on Auto-generate and new products and new variants get a barcode the moment they are created.

Which barcode format should you use?

Selling through retailers or marketplaces: use real GS1 codes (UPC-A in the US and Canada, EAN-13 almost everywhere else). The prefix must be licensed to your business by GS1.
Only for your own shop, stockroom and POS: internal codes or Code 128 are fine. They scan perfectly but are not registered to you anywhere else.

Read UPC vs EAN vs GTIN for the details.

Check before you print

A code that does not fit its format will either fail to print or scan as another number. SGT checks every code against the chosen barcode format before printing and lists any variant that would not scan correctly, so you can fix it first.

Prefer video? Watch the 90-second SGT tour on YouTube.