Your Meta Ads dashboard shows 150 conversions.
GA4 shows 95. Your CRM recorded 110.
Which number is real? The annoying answer is: they can all be “real” because they’re using different rules for who gets credit, and for how long. This is where attribution window comes into picture.
An attribution window is the time after someone clicks or views your Meta ad during which Meta can credit that ad for a conversion. Change the window, and your reported conversions and ROAS can change too. Meta also learns from conversions inside that window, so it can affect optimization, not just reporting.
What is an Attribution Window?
An attribution window is the period of time when a conversion can still be credited back to an ad interaction (a click, a view, or sometimes a video engagement). In Meta, it usually means “if someone clicked or viewed your ad, and then converts within X days, Meta counts it.”
Attribution window ≠ when the conversion happened
The conversion happens when it happens.
The attribution window decides whether the ad still gets credit for it.
So if someone buys on Friday, Meta might credit the purchase to an ad they clicked on Monday, if your window allows it.
Think of it like an ad’s memory span
Your attribution window is your ad’s “memory span.”
Short memory means fewer conversions credited to ads, even if ads helped.
Longer memory means more credit, but it can also pull in conversions that would have happened anyway.
Attribution Window vs. Lookback Window: What’s the Difference?
People mix these up because they’re basically cousins.
- Attribution window usually shows up inside ad platforms (Meta Ads, Google Ads). It controls how the platform credits conversions to ad interactions.
- Lookback window shows up in analytics tools (like GA4). It controls how far back a touchpoint is eligible to receive credit.
| Term | Where you see it | What it controls |
|---|---|---|
| Attribution window | Ad platforms | Which ad interactions get conversion credit |
| Lookback window | Analytics platforms | Which past touchpoints can receive credit |
How Attribution Windows Work in Meta Ads?
Meta doesn’t just “count conversions.” It counts conversions based on an attribution setting, then shows you results through that lens.
Meta’s current default setting
For most advertisers, the default is 7-day click and 1-day view. That means Meta can credit conversions that happen within 7 days of a click, or within 1 day of a view.
You can still compare other settings in reporting, including 1-day click and 28-day click, depending on eligibility and where you’re viewing results.
What “7-day click” actually means
Someone clicks your ad on January 1.
They buy on January 6.
Meta credits that purchase to the ad because it happened within 7 days of the click. If they buy on January 10, that purchase falls outside 7 days, so it will not be credited under a 7-day click setting.
This is one of the biggest reasons Meta often shows more conversions than GA4, because GA4 is usually stricter about what counts as an attributable touchpoint.
What happened to 28-day windows?
Meta shortened attribution options after iOS privacy changes (ATT and iOS 14.5 era). That’s why many teams went from “28-day click” habits to 7-day click defaults, and saw conversions “drop” overnight even when sales didn’t.
The important point: the business didn’t break. The counting rules changed.
Click-through vs. View-through vs. Engaged-view
Meta credit can come from different kinds of interactions. Here’s what each means in plain language:
- Click-through: credit after someone clicks your ad, then converts within the click window.
- View-through: credit after someone only sees your ad, then converts within the view window.
- Engaged-view: credit after someone meaningfully watches your video, then converts within the engaged-view window.
Now for the spicy part.
Vaizle covered a recent Meta documentation update that clarified “click” attribution can include any click interaction, not just link clicks. That can include actions like likes, shares, and saves.
If you’ve ever said “how did we get click conversions with no traffic,” that’s one reason.
| Attribution type | What triggers it | Where teams get misled |
|---|---|---|
| Click-through | Click, then convert in X days | “Click” might not mean “website visit” (Vaizle) |
| View-through | View, then convert in 24 hours | Inflates compared to last-click tools |
| Engaged-view | Video engagement, then convert | Easy to overcredit on retargeting |
Why Attribution Windows Matter for Meta Advertisers?
Attribution windows are not just a reporting preference. They change what you believe, and what Meta learns.
1) They control what you see in reporting
Your “Results” column in Ads Manager is based on your attribution setting. So when someone says “Meta performance dropped,” the first question is: “Did the window change?”
Same campaign, same spend, same buyers.
Different attribution window, different conversion totals.
If you want proof inside Meta, use the Compare Attribution Settings view to see how conversions shift under different windows.
2) They control how Meta optimizes your ads
Meta learns from conversions inside your chosen attribution window. With a 7-day click setting, Meta explicitly learns from conversions that happen within those 7 days.
Here’s the practical impact:
- Shorter windows push Meta toward “fast converters.” Great for impulse buys and strong retargeting.
- Longer windows can keep more conversions “eligible,” which can help for considered purchases, but it also blurs what actually drove the sale.
If your product takes 10 to 20 days to decide, a short window can make Meta look worse than it is.
But a long window can make Meta look better than it deserves.
3) They create cross-platform reporting discrepancies
Meta, GA4, Google Ads, and your CRM do not use the same defaults. So your dashboards disagree even when your tracking is fine.
Here’s a simple baseline table you can use in team conversations:
| Platform | Typical default window | What it means |
|---|---|---|
| Meta Ads | 7-day click, 1-day view | Credit after click within 7 days or view within 1 day |
| GA4 | 30 days for acquisition, 90 days for other key events | How far back touchpoints can receive credit |
| Google Ads | Click-through window often set to 30 days (customizable up to 90) | Conversions counted after ad interaction within that period |
| CRM | No “window,” just recorded outcomes | Usually closer to last-touch reality |
Key takeaway: If you compare numbers without aligning rules, you’re basically grading four students on four different tests.
Common Attribution Window Mistakes (And How to Avoid Them)
This is where most teams lose weeks.
Mistake 1: Using default settings without thinking
Default 7-day click, 1-day view is fine for many ecommerce brands. It’s not magic, and it’s not universal.
A B2B SaaS demo funnel can take 14 to 45 days to close.
An impulse buy (low-cost skincare, snack brands, mobile accessories) can convert in hours.
Do this instead: match your window to your typical conversion lag, not to what Meta picked for the average advertiser.
Mistake 2: Changing windows mid-campaign
When you change attribution windows, you change what gets counted going forward. That makes before-and-after comparisons messy, and it can confuse anyone reading your reporting.
Do this instead: change windows between phases. For example, after a 2-week learning period, or when you switch from prospecting to retargeting.
Mistake 3: Not aligning windows across platforms
If Meta is counting 7-day click plus 1-day view, and GA4 is looking back 90 days, your weekly report turns into a debate. Nobody trusts anything, so decisions slow down.
Do this instead: decide what your “decision window” is for budget calls, then use comparisons to translate Meta numbers into that same frame.
Mistake 4: Ignoring what your data actually shows
You don’t have to guess. Your business already has a conversion timeline.
If most purchases happen within 3 days of first touch, a 7-day click window is usually plenty.
If most purchases happen after day 10, short windows will undercount.
Checklist box: Before you touch attribution settings
- Check how long it usually takes customers to buy
- Pick one window for a full testing cycle
- Compare Meta vs GA4 vs CRM using the same reporting period
- Watch traffic metrics like Landing Page Views and Outbound Clicks, not just conversions
How to Choose the Right Attribution Window for Your Business?
No templates here. Use a simple decision framework.
Step 1: Analyze your actual conversion timeline
Start with one question: how long does it take a new visitor to become a buyer?
If you have ecommerce, use order timestamps and first-touch timestamps.
If you have leads, use form-submit date and opportunity-created date.
Look for median time to convert and a “long tail” number like the 75th percentile. That tells you whether you’re dealing with fast conversion or slow consideration.
Step 2: Match the window to your product type
Use this table as a starting point, then adjust based on your data.
| Product type | Typical behavior | Good starting point |
|---|---|---|
| Quick decision (impulse) | Converts same day or next day | 1-day click or 7-day click, limited view |
| Medium consideration | Converts over a few days | 7-day click, 1-day view |
| Long sales cycle | Converts over weeks | Use Meta for directional signals, validate with CRM and first-party tracking |
Meta can’t perfectly measure a 45-day sales cycle with a short window.
So don’t force it.
Step 3: Account for your campaign goal
Prospecting and retargeting behave differently.
- Prospecting: you need more time for people to think, compare, and come back.
- Retargeting: you’re often dealing with ready buyers, so shorter windows can reflect reality better.
If you’re launching a new product, you’ll also see longer lags at first.
People need time to trust it.
Step 4: Test and monitor
Don’t “switch and pray.” Compare.
Meta lets you compare reported conversions under different attribution settings in reporting. Use it to see how sensitive your account is to window changes.
Then sanity check against something that is harder to fake:
- Landing Page Views
- Outbound Clicks
- UTMs in GA4
- CRM outcomes
Vaizle’s Oct 2025 note about click attribution is useful here. If click conversions can include likes and saves, you want traffic columns beside conversion columns.
Conclusion
Here’s what you need to understand: Attribution windows create a reporting problem, not a settings problem. The same week can look “up” in Meta, “flat” in GA4, and “down” in your CRM because each system is using different credit rules.
Vaizle’s AI agent fits here as the layer where you standardize how you review Meta Ads performance, so you stop making budget calls based on whichever dashboard looks best today.
How Vaizle can help in practice:
- Keep Meta performance reporting in one place, so you can spot when swings are caused by measurement changes, not demand changes.
- Build a weekly review that pairs conversions with traffic signals (like landing page views and outbound clicks), so “more conversions” has context.
