{"id":14139,"date":"2026-09-03T14:20:00","date_gmt":"2026-09-03T12:20:00","guid":{"rendered":"https:\/\/www.lukaswojcik.com\/blog\/?p=14139"},"modified":"2026-10-09T22:56:24","modified_gmt":"2026-10-09T20:56:24","slug":"ga4-form-tracking-how-form_start-and-form_submit-are-counted-and-what-their","status":"publish","type":"post","link":"https:\/\/www.lukaswojcik.com\/blog\/en\/digital-analytics\/ga4-form-tracking-how-form_start-and-form_submit-are-counted-and-what-their\/","title":{"rendered":"GA4 Form Tracking: How form_start and form_submit Are Counted and What Their Ratio Does Not Show"},"content":{"rendered":"

Google’s tutorial on generating leads sets out four measuring points for a form on a website: how many people arrive at the site, how many reach the form, how many begin filling it in, and how many submit it. Three of the four rest on events that Google Analytics collects without a line of extra code, and the tutorial recommends holding the last two against each other to find weaknesses in the form.<\/p>\n

That comparison deserves a second look. The enhanced-measurement reference defines the two events in one line each. form_start<\/code> fires the first time a user interacts with a form in a session<\/em>. form_submit<\/code> fires when a form is submitted. One of the two carries a per-session cap, the other does not.<\/p>\n

\n\"Two
Two sessions, two starts, three submits. The quotient the tutorial suggests comes out at 150 percent, while the share of visitors who finished is 50 percent.<\/figcaption><\/figure>\n

Where the four numbers come from<\/h2>\n

The first two measuring points both rest on page_view<\/code>. That event is collected automatically for every web data stream, and it is the one enhanced-measurement option that cannot be switched off. Visits to the site and views of the page carrying the form are two readings of the same event, separated by the page location.<\/p>\n

The last two come from the Form interactions option in enhanced measurement, set per data stream under Admin, then Data collection and modification, then Data streams. Changing the switch requires Editor rights or above on the property. Both events read the form element itself: form_id<\/code> from its id attribute, form_name<\/code> from its name attribute, form_destination<\/code> from the address the form posts to. form_submit<\/code> adds one more, form_submit_text<\/code>, the label printed on the button.<\/p>\n

One start per session, one submit per submission<\/h2>\n

The asymmetry becomes visible as soon as two sessions are written out side by side.<\/p>\n\n\n

Text<\/span>