As management master Peter Drucker said, “What gets measured, gets managed.” Apply that to managing and optimizing your mobile ad revenue, and you’ll learn to measure what matters with on-point metrics.

Got your calculator handy? It’s time to break out your old Texas Instruments standby (okay, your favorite app works too) and get down to business with a little calculating.


This metric has been a part of the advertising world for ages. Effective cost per mille, or eCPM, is used to determine the cost of advertisements (whether they’re in newspapers, magazines or mobile apps) per every one thousand impressions.

How to Find It

To calculate eCPM, simply divide your ad revenue by the total number of impressions. Multiple this number by 1000.

For example, let’s say your ad took in $1,870 in revenue and achieved 10,000 views in the allocated period of time. Divide $1,870 by 10,000 and you’ll have 0.187. Multiply this number by 1,000. This brings your eCPM to $187 (per every 1,000 impressions).

What’s It Good For?

  • Testing the performance of different ad formats, positions and styles
  • Comparing monetization solutions on the market

Fill Rate

Yes, we’re talking about fill rates again. This rate reveals how many of your requested impressions were actually shown to users.

Seriously, this metric is vital to optimizing your mobile ad revenue. What’s the sense in throwing away impressions and earning potential?

How to Find It

To find the fill rate, divide the number of impressions displayed by the number requested. Multiply the resulting number by 100 to find the exact percentage.

If you requested 1000 impressions by your ad network and only 800 were fulfilled, the fill rate would be a mediocre 80 percent. Remember—when it comes to fill rates, keeping it at 100 is a must.

What’s It Good For?

  • Maximizing your ROI
  • Maintaining inventory

Click-Through Rate (CTR)

Of course, you want users to see the ads. But what they do afterward matters. Do they stare off into the abyss, check their Facebook newsfeed or actually click on the ad? Add the click-through rate to your metric arsenal, and you’ll be closer to finding out.

How to Find It

This metric’s a breeze to solve for. Just divide the number of clicks by impressions, and you’ve got your CTR.

What’s It Good For?

  • Studying your conversion rate
  • Determining the performance of your CPC or CPA campaign
  • Comparing CTRs for ads placed on the web vs. in-apps

Customer Acquisition Cost (CAC)

How much green do you have to put out to attract a new user? The CAC metric answers this question for you in a flash.

How to Find It

Thankfully, this one doesn’t require an advanced degree in mathematics. Take your marketing costs to obtain new users during a selected time period and divide it by the number of customers acquired.

If you spent $800 on acquisition and took in 750 new users, your CAC would come out to be $1.06.

What’s It Good For?

  • Analyzing the performance of conversion tactics
  • Maintaining profit by achieving a lifetime value for each customer higher than the acquisition cost

Average Revenue Per User (ARPU)

Each user is making you money – and knowing how much is important so you can budget, sure, but also so you can start figuring out how to drive those revenue numbers up. Time to whip out the ARPU metric.

How to Find It

Determine your total revenue for an allocated time period—a week, a month, galactic years or what have you. Divide this figure by the total number of users active during this time period.

What’s It Good For?

  • Determining upwards and downwards trends
  • Budgeting ad-spend
  • Predicting revenue generation
  • Ready for some non-calculator-required tips? We’ve a powerhouse of ideas for how to maximize your mobile ad revenue.