How to add size options to products on Shopify

Shopify lets you add size as a variant — a version of the same product that differs only in size. When you set this up correctly, customers see a dropdown menu or button group on the product page, pick their size, and add that specific version to their cart. The store tracks inventory separately for each size, so you know when small is out of stock but medium is still available.

You do this through the product editor, not through a separate settings page. Every product can have variants, and size is the most common variant type. The process takes about five minutes per product once you understand the steps.

Key Takeaways

  • Variants are different versions of the same product — in this case, the same item in different sizes — and Shopify tracks inventory for each size separately.
  • You add size variants by editing the product, clicking "Add options", naming the option "Size", and entering each size you offer.
  • After you create the option, Shopify automatically generates a variant for every combination of size (and any other options like color), and you can set a different price or inventory count for each one.
  • Customers see size choices as a dropdown menu or button group on the product page, depending on your theme's design.
  • If you have many sizes or many products, you can upload variants using a CSV file instead of entering them one by one.

Opening the product editor and finding the variants section

Log into your Shopify admin and go to Products in the left sidebar. Click the name of the product you want to add sizes to. You will see the product details page with sections for title, description, images, and pricing.

Scroll down until you see the Variants section. It usually appears below pricing and above the search engine listing preview. If you have never added variants to this product before, it will show a single variant labeled "Default Title" with no options yet. Click the Add options button or link in that section.

Creating the size option and entering your sizes

A dialog box or new section will open asking you to name your first option. Type Size in the option name field. Shopify will suggest common option names like "Color" or "Size" — you can click "Size" if it appears, or just type it yourself.

Below the option name, you will see a field or list where you enter the actual sizes you offer. Type each size on a new line or in a separate field, depending on your Shopify version. Common entries are "XS", "S", "M", "L", "XL", "XXL" for clothing, or "6", "7", "8", "9", "10", "11", "12" for shoes. Enter only the sizes you actually stock — do not add sizes you do not plan to sell.

After you enter all sizes, click Save or Done. Shopify will create a separate variant for each size you listed. If you also have a color option, Shopify will create a variant for every combination — for example, if you have sizes S, M, L and colors Red, Blue, you will have six variants total (S-Red, S-Blue, M-Red, M-Blue, L-Red, L-Blue).

Setting price and inventory for each size

After you create the option, the Variants section will show a row for each size. You can now set a different price, cost, or inventory count for each one if you need to. For example, you might charge more for XL sizes, or you might have only two units of size S in stock but ten units of size M.

Click on a variant row to expand it and see all the fields. Change the price in the Price field if this size costs more or less than your base price. Update the Quantity field under inventory to match how many units of that size you have on hand. If you do not change these, Shopify will use the base price and inventory count you set at the top of the product page for all sizes.

You do not have to set individual prices or inventory counts — many stores charge the same price for all sizes and update inventory in bulk. But the option is there if you need it.

How customers see and choose sizes on the product page

When a customer visits your product page, they will see the size option displayed as either a dropdown menu or a set of clickable buttons, depending on which Shopify theme you are using. They click or select their size, and that choice stays selected when they add the product to their cart.

If a size is out of stock, most themes will either gray it out or hide it entirely, so customers cannot accidentally order something you do not have. The cart and checkout will show the size they selected, so there is no confusion about what they are buying.

Adding more options beyond size

If you want to offer both size and color, or size and material, you can add multiple options to the same product. Go back to the Variants section and click Add options again. Name the second option "Color" or "Material" and enter the choices. Shopify will automatically create variants for every combination.

Most stores use two or three options per product — size and color is common, size and material less so. If you add too many options, the product page becomes cluttered and customers get confused. Stick to the choices that actually matter to your customers.

Uploading variants in bulk with a CSV file

If you have dozens of products or hundreds of variants, entering them one by one takes too long. Shopify lets you upload variants using a CSV file, which is a spreadsheet format that Shopify can read.

Go to Products in the admin, then click the Import button. read Shopify's CSV template, fill in your product data including the variant information, and upload the file. This is faster than the product editor for large batches, but it requires you to format the data correctly. Shopify's import guide walks you through the exact column names and order you need.

For most small stores, adding sizes through the product editor is simpler and faster. Use the CSV import only if you are adding variants to more than ten products at once.

Frequently Asked Questions

Can I change the size names after I create them?

Yes. Go back to the product editor, find the Variants section, and click the option name "Size" to edit it. You can change individual size names, add new sizes, or remove sizes you no longer offer. If you remove a size that has inventory, Shopify will warn you before you delete it.

What happens if I add a size but do not set inventory for it?

Shopify will assume you have unlimited stock of that size and will let customers order it even if you have not received it yet. Set the inventory count to zero if you want to hide the size, or enter the actual number of units you have on hand.

Can I use size variants for digital products?

Technically yes, but it does not make sense for most digital products. Size variants are useful when you ship physical items in different sizes. For digital downloads, you would normally offer one version. If you do need variants for digital products, Shopify will still create them — just do not set inventory, since digital products do not run out.

How do I delete a size option I no longer need?

Go to the product editor, find the Variants section, and click the option name "Size". You will see a delete or remove button. Click it, and Shopify will remove that option and all its variants from the product. You will lose any inventory or pricing data you set for those variants, so be careful.

Do I have to use the same sizes for all my products?

No. Each product can have its own set of sizes. A shirt might have S, M, L, XL while a hat might have One Size, and shoes might have 6 through 13. Shopify does not require consistency across products.