To add a size chart to print-on-demand products on Shopify, give each blank its own chart and show it in a popup next to the size picker, with inches or centimeters chosen by the shopper's country. You can do that with an app, your theme's own popup, or a block of Custom Liquid code. This guide compares the options, then walks through the code route, which takes three steps and no app.
The measurements in this article come from each manufacturer's published specifications for five blanks that POD stores commonly sell. We use the same data in our free Shopify Size Chart Builder.
Give each blank its own chart
POD stores often sell more than one blank, and the size labels match across brands. The garments do not. Here is size M for five popular blanks, measured flat:
| Blank (size M) | Fit | Chest width | Body length |
|---|---|---|---|
| Bella+Canvas 3001 | Classic | 20 in / 50.8 cm | 29 in / 73.7 cm |
| Gildan 64000 | Modern classic | 20 in / 50.8 cm | 29 in / 73.7 cm |
| Gildan 5000 | Classic | 20 in / 50.8 cm | 29 in / 73.7 cm |
| Comfort Colors 1717 | Relaxed | 20¼ in / 51.4 cm | 28 in / 71.1 cm |
| Next Level 3600 | Regular | 20½ in / 52.1 cm | 29 in / 73.7 cm |
Three of the five match at size M. Comfort Colors 1717 is a quarter inch wider and a full inch shorter, and Next Level 3600 is half an inch wider. Chest width is measured flat across the front, so 20 inches means about 40 inches around the garment.
The size ranges differ as well. Bella+Canvas 3001 runs XS–5XL, Gildan 5000 starts at S, Comfort Colors 1717 stops at 4XL, and Next Level 3600 goes up to 6XL in select colors. One shared chart for every tee in your store will show the wrong numbers for some products and list sizes that others do not come in.
Choose how to show the chart
There are four common ways to put a size chart on a Shopify product page. They differ most in setup effort, whether each blank gets its own chart, and whether the unit follows the shopper's country.
| Option | Setup | One chart per blank | Unit by country | What to watch |
|---|---|---|---|---|
| Size table in the product description | Paste into each product | Yes, product by product | No | Long tables push the description down and drift out of sync across products |
| Size chart app | Install and configure | Depends on the app | Depends on the app | Check the pricing and what the app loads on your storefront |
| Theme popup with page content | Theme editor | One per product template | No, without custom code | Works well for a single static chart |
| Custom Liquid code | Paste once per product template | One per product template | Yes | To change the chart, you replace the code |
If you sell one or a few blanks and want a clean popup without another app, the Custom Liquid route is the lightest option. If you have hundreds of products across many blanks and want the right chart picked automatically, an app or a setup that reads the chart from product metafields scales better.
Add a size chart with Custom Liquid
This works in themes that offer a Custom Liquid block in the product information area, including Shopify's Horizon and Dawn. Try it on an unpublished duplicate of your theme first if you prefer.
- Copy the code. Open the Shopify Size Chart Builder, choose your blank, and click Copy code.
- Add a Custom Liquid block. In Shopify admin, go to Online Store > Themes > Customize and open your product template. In Product information, add a Custom Liquid block, paste the code, and drag the block next to the size picker.
- Save and test. Save the template, open a product that uses it, and click Size Guide.
The chart appears on every product that uses that template. If products made on different blanks share one template, create a product template for each blank, paste the matching code into each one, and assign each product to its template from the product page in Shopify admin.
The popup follows your theme's text color, font, and background. Shoppers in the United States, Canada, the United Kingdom, Ireland, Australia, and New Zealand see inches first, and everyone else sees centimeters. A switch in the popup lets them change units at any time.
Check it before you publish
- Switch countries. If your store sells to more than one market, change the country in your storefront's country selector and reopen the chart. The default unit should change between inches and centimeters.
- Open it on a phone. The table should scroll inside the popup, and the popup should close with the close button or a tap outside it.
- Remove the old table. If your product descriptions already include a size table, remove it so shoppers see one set of numbers in one place.
- Recheck after theme updates. Custom Liquid blocks are saved with your theme editor settings, which Shopify usually carries into an updated theme. Confirm the block is still there after an update, as covered in what to check when a theme update loses customizations.
If the Size Guide button does not appear
- The product uses another template. Check which template the product is assigned to, and add the block to that template.
-
Shopify reports a Liquid error when you save. Part of the code was probably lost while copying. Copy it again from the builder and replace everything in the block. The full code ends with
{%- endif -%}. - Your theme has no Custom Liquid block in Product information. If it offers a Custom Liquid section instead, add that section directly below the product information. The Size Guide button then sits below the product details instead of next to the size picker. Older themes without Online Store 2.0 support need the code added to the product template files.
If you prefer to write your own version in Horizon, our guide to a country-aware size chart without an app walks through the code. If the chart still does not show up, our Shopify Bug Fix service can find the cause and get it working on your store.