Google Ads and Meta Ads attribution windows in Bangalore: why your conversion counts never match

Your Google Ads and Meta Ads dashboards rarely agree on how many sales you made, and the reason is usually not fraud or bad tracking. Each platform counts a conversion inside its own attribution window, a fixed number of days after a click or a view during which it is allowed to claim credit, and Google's default window is not the same length as Meta's. Compare the two totals directly and you are comparing two different measuring periods, not two views of the same sale.

What is an attribution window, in plain terms

An attribution window is the stretch of time a platform will look back from a conversion to decide whether an ad interaction caused it. If someone clicks your ad on a Monday and buys on the following Sunday, whether that sale counts depends entirely on whether the window is long enough to reach back six days. A platform with a longer window catches more of these sales. A platform with a shorter one does not, even when the same customer bought the same thing through the same click.

Why Google and Meta rarely agree on one campaign

Google Ads sets the default click-through conversion window at 30 days, and lets you adjust it, according to Google's own conversion window documentation, which recommends a window of at least 7 days so the account has enough conversion data to learn from. That 30-day figure is separate from which touchpoint gets the credit inside that window, a setting Google calls the attribution model, now data-driven by default across most conversion actions.

Meta works on a shorter clock. A new ad set defaults to a 7-day click and 1-day view window, set at the ad set level in Meta's Business Help Center. A view within a day of seeing the ad, without a click, can still count.

Put a real sequence through both systems and the mismatch becomes obvious. A shopper sees your Meta ad on a Monday and clicks it. On Wednesday they search your brand name and click a Google ad instead. They buy on Thursday. Meta claims the sale because it happened within its 7-day click window. Google claims it too, because the purchase happened inside its 30-day window and closer to the second click. One sale, two dashboards, two claims of credit, as a paid-ads reporting guide from Cometly walks through in more detail. Add both platforms' reported conversions together and you have overcounted your actual sales, sometimes by a wide margin.

What changes if you stretch or shrink the window

A longer window is not automatically the honest one. It is simply a different trade-off. Extending Google's click-through window from 7 days to 30 catches slower buyers, people who click today and come back to purchase three weeks later after comparing two more agencies. That matters for a service like a diploma course or a surgery consultation, where nobody decides in one sitting. It matters less for a same-day food order, where a 30-day window mostly adds noise: clicks that had nothing to do with the eventual purchase, credited anyway because they happened to fall inside a generous window.

Shortening a window does the opposite. It undercounts real conversions that simply took longer than the window allows, which can make a campaign look worse than it is and push you to cut spend on something that was working, just slowly.

What to do about it with one person watching both dashboards

Match the window to how long people take to decide, not to whichever setting makes the number look best this month. Pull Google's time lag report before picking a window. If most of your conversions land inside 10 days, a 30-day window is mostly padding; if a real share land between 15 and 25 days, a 7-day window on the Meta side is quietly throwing away conversions Meta genuinely helped cause, just outside its own clock.

Stop adding Google's and Meta's conversion totals together and reporting the sum as your total sales. Look at actual revenue or bookings instead, the number that does not care which platform wants credit for it, and treat each platform's own reported conversions as a directional signal about that platform, not as a count you can total across accounts. If a client or a manager asks why the two numbers don't add up to the real total, this is the honest answer: they were never counting the same thing to begin with.

None of this needs a paid attribution tool to start. It needs someone to open both settings pages, write down what window each is set to right now, and stop assuming they match. For a Bangalore business running both platforms on a modest budget, that half hour of checking is worth more than another dashboard subscription. Studio Happens builds Google and Meta Ads campaigns with this kind of reporting hygiene built in from the setup stage, rather than discovered three months in when a client asks why the numbers don't match. A related read on this blog covers how to split a limited ad budget between Google Ads and Meta Ads in the first place, which is the decision that usually comes right before this one.

Frequently asked questions

Why do Google Ads and Meta Ads show different numbers of conversions?

Because each platform uses its own attribution window, the number of days after an ad interaction during which it will claim a conversion. Google's default is 30 days click-through; Meta's default is 7-day click and 1-day view. The same sale can land inside both windows and get claimed by both.

Should I just add both platforms' conversion numbers together?

No. Doing that double-counts any sale both platforms claim credit for. Use actual revenue or order numbers as your source of truth, and treat each platform's own conversion count as a signal about that platform alone.

Does a longer attribution window mean more accurate reporting?

Not automatically. A longer window catches genuinely slow buyers but can also credit clicks that had little to do with the eventual sale. Match the window to how long your customers take to decide, using the platform's own time lag data rather than guessing.

Can I change Meta's attribution window after a campaign starts?

Yes, it is set at the ad set level in Meta's Ads Manager and can be changed, though the change applies to how future reporting is calculated rather than rewriting past results.

Studio Happens, Bangalore's go-to affordable digital marketing partner, can help you get started today.