⚡ Script Offloading

What is Script Offloading?

If your store runs a lot of apps or has custom code, there's probably a pile of JavaScript loading on every page. Most of it has nothing to do with what customers actually see — it's for analytics, integrations, background tasks, and so on.

Script Offloading sorts the scripts: anything tied to visible content goes first, everything else waits. The result? Customers see your page much faster, even on heavy stores.

This is especially powerful if you have several apps installed.

Why use Script Offloading?

Faster visible content — prioritizes the scripts that render what customers see and defers the rest.
Built for heavy stores — the more apps and custom code you run, the bigger the gain.
Better Core Web Vitals — cuts the JavaScript blocking your page from appearing quickly.
No loss of functionality — deferred scripts still run; they just load after visible content.

⚙️ How to use Script Offloading

Step 1: Open Speed up

Go to Speed up.

[Screenshot: Speed up page open]

Step 2: Turn on Script Offloading

Turn on Script Offloading.

[Screenshot: Script Offloading toggle switched on]

Step 3: Apply to your theme

Click Speed up now and pick a theme to apply changes.

[Screenshot: Speed up now button and theme selection modal]

Step 4: Verify it's working

To check it's working, look in your theme code for the Script Offloading optimization file.

[Screenshot: theme code editor showing Script Offloading file]

📌 Merchant Notes

Always click Speed up now after turning this on to apply the changes.
Script Offloading delivers the biggest gains on stores with several apps installed or heavy custom JavaScript.
Deferred scripts still run normally — they just load after your visible content.
This feature requires the Expert plan.
For an overview of all optimization features, see Speed up.

Critical CSS Image Optimization