Why it happens
The app added code to your theme. Shopify's help says some apps add code to your online store theme that is not removed automatically when you uninstall the app, and asks you to check the app's listing or its developer for extra uninstall steps. Older tracking apps often pasted their pixel into theme.liquid or a snippet file.
A custom pixel was added by hand. A pixel pasted into Settings > Customer events as a custom pixel belongs to your store, not to the app. Uninstalling the app does not delete it.
Code sits in the checkout's old script boxes. Shopify's help lists theme.liquid, checkout.liquid on Shopify Plus, and the Additional scripts box in the checkout settings as places where pixel code can live, and says to remove existing pixel code manually from each place it exists.
A tag manager still holds the tags. If the app's tags were set up in Google Tag Manager, they keep firing from your container after the app is gone.
Something outside Shopify keeps sending. A server container you run with another provider, or a platform's own integration, is not part of the Shopify app, so uninstalling the app does not stop it.
Check it yourself
- 1Read the old app's listing and help for its uninstall steps. Shopify asks you to check them, because some theme code is not removed for you.
- 2In your Shopify admin, go to Settings > Customer events. Look at the app pixels and at the Custom pixels tab. Disconnect or delete any custom pixel that belonged to the old app. Deleting a custom pixel cannot be undone, so note what it did first.
- 3Go to Online Store > Themes, open the menu next to your live theme and click Edit code. Search theme.liquid and the snippets folder for the old app's name and for pixel calls such as fbq(, ttq., pintrk( or gtag(. Before you delete anything, duplicate the theme as a backup.
- 4In Settings > Checkout, the Additional scripts box has been view-only since 28 August 2025, and Shopify says additional scripts are not supported on the upgraded Thank you and Order status pages, which every store has had since 26 August 2026.
- 5If you use Google Tag Manager, open the container and pause or remove the old app's tags. Publish the container.
- 6In Meta Events Manager, open Datasets, choose your dataset and open Overview. Click the Purchase row, then View Details, and read the Event breakdown with Data source picked. Browser or Conversions API events that keep coming after the uninstall date show that something still sends.
- 7Place a test order and check in each platform's own event view that it got one purchase. Meta's browser extension can also show a leftover pixel still loading on your pages.
If purchases now count twice on one platform, read Duplicate purchases after switching tracking apps and Meta counts purchases twice.
FAQ
Does uninstalling an app remove its pixel?
Not always. Code an app added to your theme, a custom pixel you pasted and tags in a tag manager stay until you remove them. Shopify asks you to check the app's own uninstall steps for this reason.
Can I just delete every pixel I find?
No. Remove only what belonged to the old app. Your new tool, Shopify's own sales channels and other apps may rely on the rest. Duplicate the theme first, so you can go back.
Why do my purchases count twice after switching apps?
The old code and the new tool both send the same purchase, and without a shared event ID Meta cannot tell they are one. Removing the old code is usually the fix.
What if I cannot find where the code is?
Search the theme code for the old app's name and the platform's pixel calls, check Customer events and your tag manager, and ask the old app's developer. Their uninstall steps say where they put it.