Attribution Window
An attribution window is the time period after a customer interacts with an ad during which a subsequent conversion can be credited to that interaction.
What Is an Attribution Window?
An attribution window (also called a lookback window or conversion window) defines how long after a customer clicks or views your ad that a resulting purchase can still be attributed to that ad. If a shopper clicks your Facebook ad on Monday and buys on Thursday, a 7-day attribution window would credit that sale to the ad. A 1-day window would not.
Common Attribution Window Lengths
Different platforms use different default windows, and this is one of the main reasons your ad dashboards never agree with each other:
| Platform | Default Click Window | Default View Window |
|---|---|---|
| Meta Ads | 7 days | 1 day |
| Google Ads | 30 days | None (search) |
| TikTok Ads | 7 days | 1 day |
| Snapchat Ads | 28 days | 1 day |
Before Apple’s iOS 14 privacy changes, Meta used a 28-day click and 7-day view window by default. The shift to shorter windows means many merchants now see fewer reported conversions in their Meta dashboard, even when actual sales have not changed.
How Attribution Windows Affect Your Data
A longer window captures more conversions but may over-credit ads for purchases that would have happened anyway. A shorter window is more conservative and may under-count the impact of upper-funnel campaigns that introduce your brand but do not drive immediate sales.
Consider a customer who clicks a prospecting ad, browses your store, leaves, and then returns organically two weeks later to buy. With a 7-day click window, that sale is unattributed. With a 28-day window, the original ad gets credit.
Choosing the Right Window for Your Store
There is no universally correct attribution window. The right choice depends on your typical purchase cycle:
- Impulse products under $50: A 1-day or 7-day click window usually captures most real ad-driven purchases.
- Considered purchases ($50-$200): A 7-day click window works well for most Shopify stores in this range.
- High-ticket items ($200+): Longer consideration periods may justify a 14-day or 28-day window.
The key is consistency. Pick a window length and stick with it across all channels so you are comparing apples to apples when evaluating ROAS and CPA.
Attribution Windows in Detectly
Detectly captures the original UTM parameters at first visit and ties them to the Shopify order whenever it happens, giving you a complete view of the customer journey regardless of platform-imposed window limits. This means you see the true source of every order, whether the customer converted in one hour or one month.
Related terms
Click-Through Conversion
A click-through conversion (CTC) occurs when a customer clicks on an ad and then completes a purchase within the attribution window.
First-Touch Attribution
First-touch attribution is an attribution model that gives 100% of the conversion credit to the very first marketing interaction a customer had with your brand.
Last-Touch Attribution
Last-touch attribution is an attribution model that gives 100% of the conversion credit to the last marketing interaction before a customer converts.
View-Through Conversion
A view-through conversion (VTC) occurs when a customer sees an ad impression but does not click it, and later converts within a defined attribution window.
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