Track form conversion with Google Tag Manager
1. List all the form conversions you want to track and assign a Google Analytics Goal Category and Action attribute.
List multiple forms for a single conversion. For example, Start Free Trial may be possible via a landing page form, footer form, pop-up form etc. Use a consistent naming convention for the Category and Action attributes.
2. Turn on the Google Tag Manager Preview to see if it's installed correctly.
If the preview pop-up is not displaying on your website, it might mean GTM is incorrectly installed. The preview pop-up should also indicate that Google Analytics is firing. If it isn’t, install GA via GTM before proceeding.
3. Navigate to Triggers > New, then select Form Submission from Trigger Type, and All Forms from This trigger fires on to create a form submission trigger that fires on all forms.
4. Submit every form with GTM preview and record all the variables.
After submitting a form, click on Form Submit in the GTM preview – the variables should be under the Variables tab. Note down all variables, like Form ID, Form Class, and Page URL, and their values. Some values might be empty. If you don’t see Form Submit, refresh GTM preview and your website.
5. Find a unique variable for each conversion that will trigger only that conversion and no others.
For example, Start Free Trial forms may share a unique free-trial form class and Demo forms share a unique demo form class. You can have more than one unique variable per conversion. For form conversions that redirect to a success page, you may want to use the Page URL and Referrer variables. To track conversions at a form level – for example, landing page form vs. pop-up form – you’ll need a unique variable for each form. If you have trouble finding a unique variable, ask a developer to add them to the form’s HTML.
6. Create a form submission trigger for each conversion with a unique variable.
Create a trigger for each form that fires on some forms and then set the unique variable accordingly.
7. Create Google Analytics event tags for each conversion: under Tags > New > Tag Configuration, select Google Analytics: Universal Analytics.
Make sure the Track Type is set to Events with Category and Action filled in, as assigned in GTM earlier. If you want to parse extra information to your GA reports, you can add an Event Label or Value attribute. Add the corresponding form triggers for each tag. Use multiple triggers per tag if you want to group conversations together. Set the Google Analytics Settings to your GA variable. This should already be available if you have GA installed via GTM.
8. With the GTM preview open, test all your form submissions for Google Analytics Event Tags.
If your tags aren’t firing as expected, click on the tag in the GTM preview, and it should indicate why the trigger did not work. Adjust your triggers as needed. Watch out for tags that fire when they shouldn’t. This means that your triggers aren’t using unique variables. These Event tags should also be showing up on your Events report in Google Analytics. You can check under Behavior > Events.