If you run Facebook™ ads, you’ve likely noticed that when creating an ad set, Facebook™ gives you the ability to optimize for 1-day clicks or 7-day clicks – along with a few other options.
7-Day click is the default, but there’s some debate over which option works best.
Everything you need to know about conversion windows
According to Facebook:Conversions windows are a tool to help you tell us what results you value so we can find more of that type of result for you. In this guide you’ll learn what conversion windows are, how they work and how to choose the right one.
Keep in mind when switching conversion windows that we recommend letting the updated ad set run for a few weeks (of 15-25 conversions per week) so our delivery system can adjust to it. This gives us time to learn how to best deliver the ad set for the new window. After the adjustment period, we recommend letting the ad set run for at least another week or two so you can see the results with optimized delivery. This is especially important when switching to a longer conversion window since more time needs to pass for us to have all the data.
How to think about conversion windows
Conversion windows allow you to tell us what type of conversion data to use when determining who we should show your ad to. We learn what types of people convert within the window, then find more people like them. There are two aspects to conversion windows:
The length of time (ex: 1 day, 7 day)
The type of action (ex: click, view)
A conversion window is the length of time between someone clicking or viewing your ad and completing an action you’ve defined as a conversion.
Important: Conversions that happen outside your window will not be used to optimize how we show your ads.
When deciding on a conversion window, keep in mind:
Part of the point of the choice is to distinguish between conversions your ads lead to (“causal conversions”) and conversions that would’ve happened without your ads (“coincidental conversions”)
Your ad set needs at least 15-25 conversions per week for our delivery system to learn who it’s best to show your ads to, and more conversions are better – learn more
Conversions happen outside of your conversion window and may show up in your reports depending on your attribution window. We recommend aligning your conversion window to the attribution window you care about as closely as possible to understand the value your ads are driving for your business. Learn how to customize your reporting columns.Note: Attribution windows are similar to conversion windows, but for the measurement system rather than the delivery system. They tell us how long after an ad impression or click to look when reporting on actions people have taken. Although we recommend aligning these two as closely as possible (there are more attribution window options than conversion window options at this time), keep in mind that your attribution window has no effect on how our delivery system handles your ad, just as your conversion window has no effect on your reporting options.
The best way to approach your choice is to figure out how to strike a balance between optimizing for causal (rather than coincidental) conversions and getting enough conversions for our delivery system to learn from.
Causal versus coincidental conversions
The first question you should consider when making your choice is: What kind of product do I have?
For example, let’s say you’ve chosen a purchase as the conversion event your ad set is optimized for. Think about the purchase cycle for your product. Does it require a lot of consideration (ex: a car)? If so, you’ll want to use a longer conversion window since it’s not unreasonable to expect a person to click on an ad for a car and take a few weeks to consider the purchase before making it. If not (ex: an app), you’ll want to use a shorter conversion window since it’s not likely that a person who downloads an app weeks after viewing or clicking an ad was very influenced by it.
The importance of data
The second question you should consider is: How many conversions am I likely to get?
You should pick a conversion window which you think will enable your ad set to get at least 15-25 conversions per week so our delivery system can find the right people. A longer conversion window can obviously lead to more conversions, but you should balance that against the type of conversion. If the additional conversions are likely to be coincidental rather than causal, the longer window may not be a good choice.
Our delivery system (unlike our measurement system) can’t distinguish between causal and coincidental conversions, so if it’s mostly learning from people who are converting coincidentally, it’s going to get you more conversions that are likely coincidental. That isn’t a good use of your ads. Rather than increasing the length of the window when your product doesn’t warrant it, we recommend optimizing for a more common conversion event (that you still value) instead. For example, if you aren’t getting enough purchase conversions, you could switch to add-to-cart conversions. If you value the new event less, you can adjust your bid accordingly.
Choosing the right window
If you know what attribution window you want to measure with in your reports, we recommend using the corresponding conversion window (if it’s available). If it isn’t, or if you’re trying to decide between two windows (ex: some conversions might be valuable whether they fall within 1 day or 7 days of a click and you want to use whichever window gets you better results), here are ways you can test to make the right choice:
Run ad sets that are identical (it’s especially important that the bids are the same) – except for using different conversion windows – and compare the results in your reports
Run a split test if you have the resources
Run a conversion lift test if you have the resources
So if you tend to make most sales from people who click and buy right away (ie. eCommerce impulse buys), then the OFFICIAL answer is that you want to select 1-day click.
If your sales process is more drawn out, you’d select 7-days click.
Personally, I’ve seen both work and actually use it as a scaling mechanism.
If an ad set is doing well, I’ll clone it, create a new campaign, and change the click option.
But sometimes, it’s worth testing to see what happens.
What about you?