View-through Conversion

A view-through conversion is a conversion credited to an ad the user only saw — did not click — but who later converted anyway without clicking.

A view-through conversion comes from the idea that seeing an ad, even without a click, can have an effect, so if a user saw a banner and days later bought directly, part of the credit should go to that impression. The concept depends inherently on ad-impression data — the system must know who saw which ad where — and that puts it out of a web analytics tool's reach, because the ad impression happens not on your site but in the ad network. It carries two serious traps: first, a view-through conversion easily claims credit for conversions that would have happened anyway, so without incrementality testing it can make display advertising look far more effective than it is; second, the view-through window (how many days after seeing an ad a conversion is still tied to it) is usually set generously, which inflates the numbers. So a view-through conversion should be read with skepticism, and preferably beside a controlled test.