Where to add sizes in Shopify

Sizes live in your product's variants section, not in a separate menu. When you create or edit a product in Shopify, you'll see an "Options" area where you can add Size as an option, then create variants for each size you sell. Shopify then shows customers a size selector on the product page, and tracks inventory separately for each size.

The fastest way is to add sizes while you're creating the product for the first time. But you can add them to existing products too — Shopify will let you create new variants without deleting what's already there.

Key Takeaways

  • Sizes are created as variants in the product editor, under the Options section, not as a separate feature.
  • You can name your option anything (Size, Sizing, Fit), but "Size" is clearest for customers.
  • Each size you offer becomes a separate variant with its own price, SKU, and inventory count.
  • Customers see a dropdown or button selector on the product page once you've added sizes as an option.

Adding sizes to a new product

When you're in the Shopify admin and creating a new product, scroll down to the "Options" section. Click "Add options" and you'll see a field that says "Option name" — type "Size" here. Then in the "Option values" field below, type each size you want to offer, separated by commas or by pressing Enter after each one.

For clothing, common sizes are XS, S, M, L, XL, XXL. For shoes, you might use 5, 6, 7, 8, 9, 10, 11, 12, 13. For home goods or furniture, you might use Small, Medium, Large. Type exactly what you want customers to see.

Once you've entered your sizes, Shopify automatically creates a variant for each one. You can then set a different price, weight, or SKU for each size if you need to. If all sizes cost the same, you can leave the prices alone and Shopify will use the base price you entered.

Adding sizes to products you've already created

Open the product in your Shopify admin and scroll to the Variants section. Click "Add options" if you don't see it, then follow the same steps: name it "Size" and enter your size values. Shopify will create new variants for each size combination.

If your product already has variants (for example, color variants), adding size will create a variant for every combination of color and size. A shirt in red, blue, and green, with sizes S, M, L, will create nine variants total. Make sure you have inventory counts for each one, or set them to zero if you don't sell that combination.

Setting prices and inventory for each size

After you've created your size variants, click into the Variants section to see the full list. Each size (or size-and-color combination) appears as its own row. Click on any variant to edit its price, weight, SKU, barcode, or inventory count separately.

If you sell the same size in multiple colors, you can set different prices for each color if you want — for example, premium colors might cost more. You can also set inventory to zero for sizes you don't currently stock, and Shopify will hide them from the customer's dropdown until you add inventory back.

How customers see and choose sizes

Once you've added sizes as an option, customers visiting your product page will see a dropdown menu or button group labeled "Size" (or whatever you named it). They click their size before adding the item to their cart. Shopify prevents them from checking out without selecting a size, so you won't get orders with missing size information.

If a size is out of stock, Shopify can either hide it from the dropdown or show it as unavailable, depending on your store settings. You control this in your product settings under "Inventory tracking" — choose whether to show or hide out-of-stock variants.

Common mistakes when adding sizes

The most common error is forgetting to set inventory for each size separately. If you create five size variants but only set inventory on one of them, customers can only buy that one size. Check the Variants section and make sure every size has an inventory count, even if it's zero.

Another mistake is using inconsistent size names. If you type "Small" for one product and "S" for another, customers see different labels across your store and may get confused. Pick a naming system (all spelled out, or all abbreviations) and stick with it.

Don't create separate products for each size. Shopify variants are designed exactly for this — they keep all sizes of one item on one product page, which is better for search results and customer experience.

Editing or removing sizes later

If you need to add a new size after the product is live, open the product, go to Options, and click the edit icon next to "Size". Add your new size value and Shopify will create a new variant for it. You can then set its price and inventory.

If you want to remove a size, you have two choices: delete the variant entirely (which removes it from your store), or set its inventory to zero and hide it from customers. Hiding is safer if you think you might sell that size again later. To delete, click the variant and scroll to the bottom — you'll see a "Delete" button.

Frequently Asked Questions

Can I use size ranges like "One Size" or "One Size Fits All"?

Yes. Type "One Size" as one of your size values just like any other. Shopify treats it as a regular variant, so customers will still see the dropdown and select it before checkout. This works well for items like hats, scarves, or universal-fit products.

What if I sell the same product in different sizes and colors?

Add both Size and Color as separate options. Shopify creates a variant for every combination — so three colors and four sizes makes twelve variants. Each one gets its own inventory count and can have a different price if you want.

Can I change a size name after customers have already bought it?

You can edit the size name, but past orders will still show the old name. Customers won't be confused because their order confirmation email shows what they actually received. For future orders, the new name will appear. If you're changing sizes significantly, it's clearer to create a new variant and let the old one sell out.

Do I have to charge different prices for different sizes?

No. If all sizes cost the same, just enter one price when you create the product and Shopify applies it to every size variant. You only need to set individual prices if some sizes cost more — for example, larger clothing sizes sometimes have a higher price.

What happens if I run out of a size?

Set that size's inventory to zero in the Variants section. Depending on your store settings, Shopify will either hide it from the dropdown or show it as "Sold out". Customers can't buy it either way. When you restock, change the inventory number back and it becomes available again.