Facebook metrics have changed a lot over the past last years, partly due to a number of reporting issues the network has experienced. There are more changes coming in June 2018, too, as Facebook removes certain metrics and labels the remaining ones more clearly, in a bid to make campaign measurement easier for advertisers.

So now seems like a good time to clear up some metric confusion ahead of these changes. In this article, we’ve got three common areas of confusion that we’re often asked about by clients and


#1: Reach vs impressions

The first question people tend to have about Facebook metrics is: what’s the difference between reach and impressions. Thankfully, this is one is nice and easy to explain, though. Basically, it comes down to how many people have seen your ad vs the total number of times your ad has been seen.

Here’s how Facebook defines the two metrics:


  • Impressions: “The number of times that your adverts were on-screen.”
  • Reach: “The number of people who saw your adverts at least once. Reach is different to impressions, which may include multiple views of your adverts by the same people.”


Because the same person can see your ad more than once, impressions doesn’t tell you how many people saw your ad – ie: the total number of people reached. So Reach is likely to be lower than the figure you see for impressions but it should never be higher. You can use these two metrics to calculate how many time each person sees your ad on average and work out click-through rates vs total impressions and the number of people who see your ad.

Crucially, you can also use reach to calculate a more accurate conversion rate against the number of people who see your ad, regardless of how many times they see it.

Facebook also provides separate metrics for Cost per 1,000 people reached and CPM (Cost per 1,000 impressions). As you can tell by now, these give you figures for the cost of 1,000 people to see your ad vs the cost of it being seen 1,000 times, regardless of how many times individual users see the same ad.

Note: Cost per 1,000 people reached is an estimated metric based on sampling and modelling.


#2: Results vs actions

Another common area of confusion for Facebook advertisers is results vs actions and this one is a little more complex. The good news is this is one area Facebook is going to simplify in the upcoming metrics changes in June. For now, though, let’s explain the difference.

There are a lot of actions that can result from someone seeing your ad: engagement actions, clicks, website conversions, a product purchase and many more. Some of these actions are directly related to your campaign goals. For example, if you’re running a campaign for engagement, then likes, shares, clicks and various other actions are the desired result of your campaign.

Actions tells you the total number of actions attributed to your ads and campaigns while results tells you how many times your campaign goal was achieved.

Here’s the official definition of results from Facebook:


“The number of times that your ad achieved an outcome, based on the objective and settings you selected.”


Now, as we say, this is one area Facebook is about to clean up and it’s actually going to remove action metrics from reporting altogether in June. Which means actions, people taking actions and cost per any action are all going to disappear from Facebook reporting – so don’t worry if you’re still confused about the difference between actions and results.


#3: Website leads vs clicks

While website clicks is a pretty simple metric, website leads is not so straightforward, Actually, it’s easy to get caught out by this one and it doesn’t help that Facebook does a pretty poor job of explaining what the website leads metric means.

Here’s the description you’ll see in ad manager:


“The number of lead events tracked by the pixel on your website and attributed to your adverts.”


When it comes to clicks, they’re simply measured when a user clicks on your ad, link or button (there are separate metrics for clicks on these different elements). It doesn’t matter whether the same user clicks on your ad multiple, they’re all counted – except for the unique click metrics, which calculate the number of people who clicked, not the entire total of clicks.

That’s simple enough.

In the case of Website leads, which are measured using Facebook Pixel, things are more complex. The first thing you’ll notice if you have clicks and leads sitting next to each other in your reporting table is you’ll have far fewer leads than clicks – as expected. However, you’ll also notice website leads are typically lower than the number of unique clicks and sometimes the difference can be surprisingly large. This is because Facebook only attributes leads to the first visit from a user being tracked by Pixel, which doesn’t sound problematic. Until you get a campaign running four ads (let’s call them A, B, C & D) and they click ad A without converting or taking a desired action. Facebook will map this lead to ad A and if this user later sees ads B and C before finally converting after seeing ad D, these ads don’t get any lead attribution.

Due to this model of attribution, it’s possible to end up with ads that convert being attributed no leads at all, which might lead you to changing these ads or dropping them altogether because it looks like they’re not performing. More commonly, you might see an ad is generating a lot of clicks (each of which costs you money) and doesn’t generate the number of leads you need, even though it’s playing a vital role in the conversion process for you.

To get around this, you need to use a composite of metrics for clicks, leads and conversions – plus specific actions such as form leads, where possible – to get a more accurate picture of how your ads are contributing to your wider conversion goals.


We know it can be hard to get your head around the intricacies of different metrics on advertising platforms like Facebook. At first, it might seem unnecessarily complex but these nuances will help you pinpoint more specific performance indicators once you’re used to handling them. Without these, it would be impossible to diagnose a specific ad in a complex campaign that’s not performing the way it should. This is the double-edged sword of advertising metrics: they’re incredibly powerful if you know how to use them but equally as dangerous if you don’t understand them correctly.