For campaigns with a CPA rate (cost per action, which could be a sale or signup for example), the formula is very similar:

- You will need to look up the number of ad impressions over a given period of time
- You will also need to look up the number of sales or leads (we call these ‘conversions’) over the same period of time
- And finally, you will need to know the CPA rate for the campaign

** Once you know this input data, the formula is: **

- Multiply the number of conversions by the CPA rate to come up with the total revenue
- Divide the number of impressions by 1,000, giving you the number of blocks of 1,000 impressions delivered
- Divide the total revenue by the number of blocks of 1,000 impressions to come up with the eCPM value

** Let’s use the following fictional numbers as an example: **

- A campaign with CPA pricing was displayed 2 million times in a period of 1 day
- In the same day, the ad server measured 100 sales related to the banners that were displayed and clicked
- The CPA rate for the campaign was set to $ 30 per sale

** We can now calculate the eCPM of this campaign with a CPA rate: **

- Total revenue was 100 sales times $30 equals $ 3,000
- 2 million impressions equal 2,000 blocks of 1,000 impressions
- The eCPM is $3,000 divided by 2,000, equals an eCPM of $ 1.50

Like in our previous example, it is highly unlikely that there are nice round numbers like this, but the formula is always the same.

### The Revolver Ad Project will automatically calculate the eCPM for you #

Fortunately, you do not have to calculate the eCPM outcomes yourselves. In the statistics screens of your Revolver Ad Project, you can enable an extra column that will show this value automatically at all times.