Attribution Windows
1-day view, 7-day click, infinite: what changes in your numbers.
A client once sent me two screenshots of the same campaign, taken ten minutes apart. One said 212 purchases. The other said 61. Nothing had changed except a dropdown in the top right corner of Ads Manager. That dropdown is the attribution window.
The one-sentence version
An attribution window is how long after seeing or clicking an ad a purchase still counts as that ad's. Longer window, more purchases reported. The purchases themselves do not change. Only who gets to claim them.
The setup
Same ads, one dropdown
Take 1,000 people who clicked your ad. Most who buy do it the same day. Some buy a week later. A few buy in month two, after three more ads, a podcast and a text from a friend. Where you draw the line decides the number on your dashboard.
Try it: same ads, different window
How many sales does Meta report?
Click window
7 days
View-through (count a sale if they saw an ad within 1 day, no click):
Reported by Meta
94
7-day click + 1-day view
Verified ad-driven
100
matched to orders, one credit each
Roughly honest. Rare. The trick is that no single window is right for every campaign.
The ads are not doing the selling. The dropdown is doing the reporting.
Three windows, three lies
Which one does what
1-day view
Counts a sale if someone merely saw your ad yesterday. Great for claiming your own returning customers. Retargeting campaigns live on this.
7-day click (Meta default)
Reasonable for impulse products. Also counts the customer who clicked on Tuesday and bought from your email on Saturday.
30-day click (Google default)
Fine for considered purchases. Also means a brand search on day 28 gets credit for a customer Meta found on day 1.
Why it matters
Windows overlap, and overlap is double counting
Meta's 7 days and Google's 30 days are not a choice between two numbers. They run at the same time, on the same customer. A purchase can sit inside both windows and be reported twice. Add Klaviyo's 5-day open window and a single order can be reported three times, each time honestly.
The 212 vs 61 client picked 212 for the board deck. I understand why. The board did not.
The fix
Keep the window for delivery, drop it for decisions
The platforms need a window to learn from. Leave it. For budget decisions, use a system where the order is the unit, the click is kept as long as it takes, and one order can only be credited once across every channel. In TrueROAS the journey view shows you the full path with dates, so "day 28 brand search" reads as exactly that.
Honest footnote
When windows do not matter much
Sub-$50 impulse products with same-day purchase behaviour: a 1-day and a 7-day window will report nearly the same thing. The overlap problem still applies if you run more than one channel.
Questions people actually ask
Straight answers
What are Meta's default windows?
7-day click and 1-day view. You can change them per ad set. The reporting window can also differ from the optimisation window, which confuses almost everyone.
What is Google's window?
30-day click by default for most conversion actions, with 1-day engaged view for video. Adjustable per conversion action.
Should I set everything to 1-day click?
Usually no. It removes over-counting but also hides real purchases that took a few days, and Meta's delivery learns from fewer events. Keep a normal window for delivery; judge budget on verified, de-duplicated data.
What does 'infinite lookback' mean?
The attribution tool keeps the click forever and can credit an order months later. Useful for high-consideration products. It only stays honest if credit is still capped at one order and split across everything else that touched it.
See your own numbers, verified against your orders.
Free under $10k/month in revenue. 14-day trial above that. Nothing changes in your ad accounts. You will know within a week which platform has been telling stories.
"I built this because I was making $50k-a-month decisions on numbers I knew were wrong. If TrueROAS does not show you something Meta or Google got wrong in the first two weeks, tell me and I will help you cancel."
Rasmus Arvidsson
Founder, TrueROAS. Answers support himself.
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