If you use PayPal Standard to collect payments, your visitor has to leave your website to complete the transaction. That makes conversion tracking a little trickier.
To make sure that you are tracking conversions accurately, make sure that PayPal is redirecting your user back to an order confirmation or thank you page after the transaction is complete. You'll set this up when you set up your PayPal button.
Set up conversion tracking with PayPal
1. Log in to your PayPal account.
2. Navigate to "Tools".
3. Click "PayPal Buttons."
4. Any buttons that you previously created will appear here. If you are editing an existing button, click "Action" next to the button name that you want to edit. Otherwise, click "Create new button".
5. The option to redirect users back to a page on your website is in Step 3: Customize advanced features (optional). Click open this section.
6. Check the box next to "Take customers to this URL when they finish checkout" and enter your order confirmation or thank you page URL. Make sure that you verify that the URL entered is correct - if not your users will see a 404 error page.
Note that you can specify a custom page if your visitor cancels too.
7. Click "Save Changes" to confirm (or "Create Button, if new).
8. Set up a conversion audience that's tied to the URL of your conversion page.