Product display rules decide which products show a SmartSize size chart or fit quiz. Use them when you want a chart or quiz to appear only on the products it belongs to.
This guide shows a fit quiz example. Use the same basic approach when you assign a size chart.
Before you start
Make sure you have:
a size chart or fit quiz saved in SmartSize
at least one Shopify product you want to show it on
the correct SmartSize app extension turned on in your live theme
If you are setting up your first fit quiz, finish Create your first fit quiz first.
1. Open the product display rules section
Open the size chart or fit quiz you want to show on your storefront.
Find Product display rules. This section lets you select products, collections, product types, vendors, or tags.
For your first setup, start with one product. This makes the result easy to check.
2. Select one product
In Product display rules, choose Products.
Search for the product and select it. Then click Select.
SmartSize adds the product to the rule.
3. Add more products if needed
If the same size chart or fit quiz should appear on several individual products, select more than one product in the same picker.
Use this when you have a small, specific group of products.
4. Use collections for larger groups
If many products share the same chart or quiz, it is usually easier to target a collection.
Choose Collections, select the collection, and click Select.
Use collections when your Shopify store already groups products in a way that matches your sizing setup.
5. Use product types or tags for flexible targeting
You can also target products by Shopify product type or product tag.
Use Types when the same chart or quiz applies to a product category, such as dresses, blazers, or hoodies.
Use Tags when your team already uses Shopify tags to organize sizing groups, materials, or quiz types.
For your first setup, keep the rule simple. You can always add broader targeting later.
6. Check the matching products
After you select products, collections, types, vendors, or tags, SmartSize shows how many products match the rule.
Review the matching product list and confirm that the correct products appear.
If the wrong products appear, remove the rule and choose a narrower option, such as one product instead of a collection or tag.
7. Save your changes
Click Save.
The size chart or fit quiz is now assigned to the matching products.
Check the result
Open one of the matching product pages on your storefront.
You should see the relevant SmartSize button:
Size Chart for a size chart
Find my size for a fit quiz
If the button does not appear, check that:
the size chart or fit quiz is Active
the matching product is the same product you opened on the storefront
the relevant SmartSize app extension is active in your live theme
What to do next
After the basic rule works, you can create broader rules for collections, product types, vendors, or tags.
If several charts or quizzes can match the same product, use priority carefully. Priority is an advanced setting and is best handled in a separate guide.