I published a post for AgoraPulse today called Know Your Facebook Ad Metrics: Those You Use and One You Should. It’s a good overview of what all of the various Facebook ad metrics mean and how you should use them.
I felt that the bottom portion of that post was a good jumping off point for a separate post here. That portion focused on the metric you aren’t using, but you should.
The typical marketer focuses on CTR (Click Through Rate), CPMCPM measures the cost per 1,000 impressions. It's a good metric to evaluate competition level and costs to reach your audience. More (Cost Per Thousand ImpressionsImpressions are the number of times your ads were displayed to your target audience. Impressions aren't counted if it is detected they came from bots. More), CPC (Cost Per ClickFacebook reports on CPC (All) and CPC (Link Click). The first refers to all clicks and the second on all internal and outbound links. More) and number of Actions. Those are all good metrics to follow, don’t get me wrong, but they do not determine success or failure of your campaignThe campaign is the foundation of your Facebook ad. This is where you'll set an advertising objective, which defines what you want your ad to achieve. More in and of themselves.

The metric you need to be using is Cost Per Desired Action.
The Flaw of Traditional Metrics
The metric I see discussed most often related to campaign success is CTR. But the problem with such a metric is that it lacks context.
I’ve heard people say that you should look for a CTR over .5%, depending on the ad type. If you surpass 1%, that’s awesome. I’ve seen ads reachReach measures the number of Accounts Center accounts (formerly users) that saw your ads at least once. You can have one account reached with multiple impressions. More as high as 10% CTR — meaning that 10 of every 100 people who see your ad clicked on it.
Here are the problems: Fluffy clicks and a widely varying CPM and CPC.
Regular CPM could be as low as $.15. If you don’t care about quality and target the “right” countries, you can get Cost Per Action (likes) as low as $.03.
Meanwhile, you can also use the Optimized bidding methods, where Facebook targets your ad at people most likely to perform your desired action. In these cases, CPM tends to be at least a few dollars, going as high as $20 or more.
An Example
Below is a hypothetical example involving Ad #1 and Ad #2. Both ads have a Reach of 100,000, FrequencyCalculated as (Impressions/Reach), Frequency is a Facebook ads metric that measures the average number of times users have seen your ad. More of 1.5 and total Impressions of 150,000.
Ad #1: 6,500 Clicks, 4,000 Actions, 4.33% CTR
Ad #2: 2,000 Clicks, 1,500 Actions, 1.33% CTR
Which ad was more successful?
Hopefully you said: I don’t know! I need more info!
Unfortunately, most advertisers stop here, focusing entirely on CTR. But the CPM of Ad #1 is $9.50 and for Ad #2 it’s $3.00. Splits that can easily happen, particularly if Ad #1 is Optimized CPM and Ad #2 is regular CPM.
Based on that, here are a few more stats…
Ad #1: $.22 CPC, $1,425 Spent
Ad #2: $.23 CPC, $450 Spent
Which ad was more successful?
Hopefully you again said: Jon! Dude! I need more info!
Once again, many advertisers worry about the CPC. They’re on the right track, but “Clicks” typically include many uneventful things that pad the stats.
And one more stat…
Ad #1: $.36 CPA (Cost Per Action)
Ad #2: $.30 CPA
For the purpose of this example, I’m going to assume that all Actions measured here are “Desired” Actions. But understand that you may need to sort this out a bit more since depending on the ad you may get Actions that aren’t directly related to success.
In the example above, Ad #2 is more successful and efficient at driving the desired action. But such information is buried — and not displayed within the main Facebook Ads Manager interface.
Cost Per Desired Action and ROI
The reason why you want to isolate the Cost Per Desired Action is so that you can measure ROI. How many Likes, ConversionsA conversion is counted whenever a website visitor performs an action that fires a standard event, custom event, or custom conversion. Examples of conversions include purchases, leads, content views, add to cart, and registrations. More, Sales or Leads did you get per dollar spent on your ads? And how much revenue directly resulted?
Before you get to ROI, you first need to optimize your ads to determine which are most efficient at driving the desired action. Once you stop those that aren’t working and ride those that are, you can compare your cost of advertising to the direct revenue that resulted.
We don’t talk about direct ROI very often when it comes to Facebook marketing, but here is a case when it’s absolutely possible — and recommended.
Following are some examples of Desired Actions based on types of ads you may be running:
- Page Like Sponsored Story: Page Like
- Domain Sponsored Story: Link ClickThe link click metric measures all clicks on links that drive users to properties on and off of Facebook. More
- App Install Sponsored Story: App Install
- Event Sponsored Story: Event RSVP
- Facebook Offer: Offer Claim
- Page Post Ad: Comment, Like or Share*
* NOTE: If you are using offsite pixels to measure conversions (purchase, lead, form submission, key page view) that result from your Facebook ad, those conversions would represent your Desired Action.
As mentioned earlier, there is no CPDA (or CPA) metric within the Facebook Ads Manager interface, so you’ll need to calculate that manually. There are a few methods described in detail in that post I wrote for AgoraPulse.
Your Turn
How do you measure success of your Facebook ads? Do you do something similar or something completely different?
Let me know in the comments below!