eCPI: Effective cost per install.

The average cost of each install, including organic installs the ads helped bring.

eCPI is effective cost per install. It is total user acquisition spend divided by total installs in a period. Some teams count only paid installs, so state which definition you use when comparing numbers.

The formula

eCPI = total spend / total installs

For example, spending 1,000 USD in a week that brings 400 installs gives an eCPI of 2.50 USD.

Why "effective"

Paid ads often lift organic installs too, because more downloads help store ranking. Dividing spend by all installs gives the effective cost. Dividing by paid installs only gives the paid cost per install. Teams use both, so state which one you mean when you compare numbers.

How to use it

eCPI alone says little. Compare it with LTV: if a player is expected to be worth more than the install cost, a campaign can scale, and if not, it cannot. Track eCPI by country, platform and campaign, because it varies widely between them. To attribute installs to campaigns you need an MMP.

See our ads service and the article on mobile game ad creative testing.