Lead attribution

Lead attribution is knowing, for each lead, which marketing activity produced it - not in aggregate ("Google sends us traffic") but per row ("this lead came from that campaign, that keyword, that click"). It is the difference between a spreadsheet of names and a spreadsheet that can tell you which spend to cut.

Attribution data arrives in two grains. Campaign-level parameters - the UTM tags - name the source, medium, and campaign in readable text. Click-level identifiers - gclid and wbraid/gbraid for Google, fbclid for Meta, msclkid for Microsoft - are opaque tokens naming one specific click, and they unlock the deeper loop: report a closed deal back to the ad platform with its click ID, and the platform learns which clicks become revenue rather than which merely become form fills.

The engineering is mundane and unforgiving. All of these parameters exist only on the landing page URL; the visitor who browses four pages before filling in your form has lost them unless something captured the values at arrival, persisted them, and attached them to the submission. Most broken attribution is not a strategy failure - it is this capture step silently missing.

SheetLink Forms builds the capture step into the embed. sl.js reads utm_source, utm_medium, utm_campaign, utm_term, and utm_content plus gclid, wbraid, gbraid, fbclid, and msclkid from the URL, persists them in localStorage across pages, and attaches them to every submission - so each lead lands in your sheet as a row with its attribution in the columns beside it, whether the form was on the landing page or four clicks deep.

The walkthrough is in the guide on capturing gclid in forms, and the live demo shows attribution columns filling in a public sheet.