Attribution Window

Concept

An attribution window is the allowable timeframe between when a user interacts with an ad and when a resulting purchase is credited to that ad.

What is Attribution window, in plain English?

Think of an attribution window like an expiration date on a store coupon. If a customer clicks your Google ad on Monday and finally buys your product on Friday (4 days later), a 7-day attribution window says: "Yes, that ad caused the sale, give Google credit!" But a 1-day window says: "Too much time has passed, treat this sale as direct/unattributed."

Attribution window example

Meta defaults to a 7-day click / 1-day view window. If someone clicks your Instagram ad on Day 1 and purchases on Day 6, Meta reports 1 conversion. If your CRM only looks at same-day clicks, your CRM will report 0 ad conversions for that purchase.

Common Attribution window mistakes

Google Ads (30-day click default), Meta (7-day click default), and your internal database each use completely different windows. This is the #1 reason ad dashboard numbers never match your bank or database revenue.

What is a good Attribution window?

Choose a window that matches your real purchase cycle, measured from your own data as click-to-purchase lag. Impulse purchases may need only a 1–7 day click window; considered purchases need longer. Keep the window fixed when comparing periods, and state it whenever you report a platform number.

Attribution window FAQs

What are the default attribution windows in Google Ads and Meta?

Google Ads defaults to a 30-day click window for most website conversion actions; Meta's default is 7-day click and 1-day view. Your own database applies no window at all — one reason the three rarely agree.

Does changing the attribution window change results?

It changes how many conversions get credited to ads, not how many sales happened. A longer window credits more conversions, so reported ROAS rises while actual revenue stays the same.

Which attribution window should I use?

One that covers most of your genuine click-to-purchase lag without sweeping in purchases the ad didn't influence. Check the lag distribution in your own orders and pick the window that captures the bulk of it.

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