Attribution & Tracking
View-Through Attribution Impact Calculator
The View-Through Attribution Impact Calculator estimates how much of your reported ROAS comes from view-through conversions (people who saw but never clicked your ad) versus genuine click-driven results. It separates VTA conversions from click conversions, shows your reported ROAS next to your click-only ROAS, and quantifies the inflation percentage, a VTA pollution score, an incrementality estimate, and the conversions likely lost to iOS ATT. The outcome is a realistic view of what your ads are actually driving.
Who it's for: Performance marketers at DTC brands whose platform ROAS leans heavily on view-through attribution and who want to measure true click-driven return.
How the View-Through Attribution Impact works
You enter total conversions, the percentage that are view-through, ad spend, average order value, the platform, and your iOS traffic share. The tool splits conversions into view-through and click-through, then computes reported ROAS from all conversions and actual (click-only) ROAS from click conversions alone.
The difference between those two ROAS figures is expressed as an inflation percentage, and the VTA pollution score shows what share of your conversions are view-through. Because most view-through conversions would have happened anyway through organic or direct paths, the tool estimates only about 30 percent as truly incremental.
It also estimates conversions lost to iOS 14.5+ App Tracking Transparency based on your iOS traffic share, compares your VTA percentage against a platform benchmark (Meta around 40 percent, Google Display around 50 percent, and so on), and gives budget reallocation guidance that scales with how inflated your ROAS is. Inflation above 40 percent is flagged critical.
The formula
View-through conversions = total conversions x (VTA % / 100). Click-only ROAS = (click conversions x AOV) / ad spend. ROAS inflation % = ((reported ROAS - click-only ROAS) / click-only ROAS) x 100. Truly incremental VTA conversions are estimated at roughly 30% of view-through conversions.
Frequently asked questions
What is view-through attribution?+
View-through attribution credits a conversion to an ad the customer saw but never clicked, as long as they purchase within the platform's view window (often 1 day). It is useful for measuring upper-funnel awareness, but it routinely captures buyers who would have converted regardless, which inflates ROAS and makes paid social look more effective than it is.
How do I find my VTA percentage?+
In Meta Ads Manager you can break conversions down by attribution type and divide view conversions by total conversions, then multiply by 100. Google does not show this directly, but display campaigns typically run 20 to 40 percent view-through. If you cannot measure it precisely, use the platform benchmark shown in the tool as a reasonable starting estimate.
Why does the calculator assume only about 30 percent of VTA conversions are incremental?+
Incrementality research consistently shows that a large majority of view-through conversions would have occurred through organic, direct, or other channels even without the ad impression. The tool uses a conservative 30 percent incremental estimate to approximate the true lift, which is why your click-only ROAS is a safer basis for budget decisions than your reported ROAS.
How does iOS ATT factor in?+
Since iOS 14.5, users who opt out of tracking cannot be reliably attributed, which causes platforms to lose or misattribute conversions, often 20 to 40 percent of iOS traffic. The calculator applies an estimated loss to the iOS portion of your view-through conversions, so a higher iOS traffic share means a larger measurement blind spot in your reported numbers.