Attribution Window
AnalyticsAlso: Conversion Window · Lookback Window
Quick definition
An attribution window is the period of time after a user clicks or views an ad during which a conversion is credited to that ad. A 7-day click window means any purchase within 7 days of clicking your ad is counted as a conversion. Different window lengths produce different conversion counts from the same campaign.
Try the same spend with conversions at 1-day, 7-day and 28-day window counts to see how the window choice changes your reported CPA. The spend is fixed. Only the window moves.
How it varies across Australia
Most Australian advertisers run the platform default window without reviewing whether it matches their actual sales cycle. The mismatch between a short sales cycle and a long window inflates reported conversions. The mismatch between a long sales cycle and a short window understates them. Neither is free.
See data and tracking scores across Australian industries →The two window types
Counts conversions within N days of a user clicking your ad. Standard across all platforms.
Common settings: 1, 7 or 28 daysCounts conversions within N days of a user seeing (but not clicking) your ad. Controversial because the causal link is weakest here.
Common settings: 1 or 7 daysWhat it actually means
Every ad platform needs a rule for which conversions belong to which ad. The attribution window is that rule. When someone clicks your ad on Monday and buys on Friday, a 7-day window claims the sale. A 1-day window misses it. Same customer, same journey, different reported result.
The window is set by you, usually in the campaign or ad account settings, and most teams never change the platform default. That default is almost always designed to maximise credited conversions, which means maximise the platform's apparent ROI, which means maximise your next budget transfer to them. The incentive is not neutral.
View-through windows make this more extreme. A view-through conversion credits your ad if someone merely saw it before converting, with no click required. A customer who saw your display ad three weeks ago and then searched for you directly gets counted as a conversion. Whether your ad caused that conversion is a question view-through attribution doesn't try to answer.
The practical impact is that changing your window setting is one of the fastest ways to make your CPA look better or worse without changing anything about actual performance. That makes it a risk in reporting and an opportunity in honest analysis.
The window setting is the volume knob on your reported conversions. Longer window, louder number. The signal doesn't change.
How to calculate it
Credited conversions = all conversions within N days of a qualifying click or view
Worked example. Your campaign ran for a month. Total site purchases were 300. Of those, 180 happened within 1 day of a click, 240 within 7 days, and 270 within 28 days. A 1-day click window reports 180 conversions. A 7-day window reports 240. A 28-day window reports 270. The campaign performance looks different under each setting, but the actual purchases don't change.
The Australian context
Australian advertisers in considered-purchase categories like finance, property and health tend to have longer sales cycles than the platform default windows assume. A 7-day click window will undercount conversions for a mortgage broker whose lead-to-settlement cycle runs weeks. A 28-day window will overcount for an ecommerce brand whose abandoned-cart buyers come back within hours.
Australia's Privacy Act amendments also affect view-through tracking specifically. Cross-site tracking limitations introduced through browser changes (particularly Safari's Intelligent Tracking Prevention) reduce the accuracy of view-through measurement for Australian audiences using Apple devices, which account for a material share of mobile traffic.
Where people get this wrong
Related terms
Common questions
What attribution window should I use?
Match the window to your sales cycle. If most of your customers convert within a day of clicking, a 1-day click window is honest. If your sales cycle runs a week or more, a 7-day window makes sense. The test is what your CRM says about time-to-conversion, not what the platform defaults to.
Why does changing the attribution window change my CPA?
A longer window captures more conversions. With the same spend and more reported conversions, reported CPA falls. The actual conversions and the actual spend don't change. Only the accounting does.
Should I use a view-through window at all?
Use it cautiously, if at all. View-through windows credit conversions where no click happened, which conflates ad exposure with ad causation. If you run one, keep it short (1 day) and run an incrementality test alongside to verify the conversions are real.
Why do my ad platform numbers not match my Google Analytics numbers?
Different attribution windows are one of the main reasons. Google Ads defaults to a 30-day click window. Google Analytics 4 uses a much shorter session-based model. The same conversion falls inside one window and outside the other. Neither is lying. They're counting differently.
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About New Rebellion
New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.
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