Problem
If SmartSize is loading on pages where it isn't needed—such as your homepage, landing pages, collections, or blog posts—it can contribute to unnecessary JavaScript execution and increase page load times.
If you only use SmartSize on product pages, you can configure the app to load its storefront script only where it's needed.
Solution
SmartSize includes a Script loading setting that lets you choose which storefront pages load the SmartSize script.
To change this setting:
Open Shopify Admin.
Go to Apps → SmartSize → Settings.
Scroll down to the Script loading section.
Select Product pages only.
Save your changes.
This prevents the SmartSize script from loading on non-product pages, helping reduce unnecessary JavaScript and improve storefront performance.
Recommended: Select Product pages only if your size charts and fit recommendations are only used on product pages.
Where to Find the Setting
Benefits
Restricting SmartSize to product pages can help:
Reduce JavaScript execution on non-product pages.
Lower Total Blocking Time (TBT).
Improve Lighthouse and PageSpeed Insights scores.
Improve Core Web Vitals on landing pages.
Reduce unnecessary network requests.
Frequently Asked Questions
Will this affect my size charts on product pages?
No. Size charts and fit recommendations will continue to work normally on product pages.
Should I use "All pages" instead?
Only if you've intentionally implemented SmartSize outside of product pages (for example, via custom buttons or links elsewhere on your storefront). Otherwise, we recommend Product pages only for the best performance.