Back to Glossary

Ad-Impression

Description

An ad impression is counted when an ad is fetched and displayed to a user.

Definition

It's the basic unit of ad delivery—each time an ad loads on a user’s screen (whether viewed or not), it counts as an impression.

Why Is Ad-Impression Important for App Marketers?

It’s foundational for CPM billing, reach calculation, and impression-based campaign performance.

Where You Can Use Ad-Impression

CPM campaigns, viewability tracking, ad servers, mediation layers, programmatic reporting.

What Are the Best Practices

  • Focus on viewable impressions, avoid auto-refresh abuse, segment by geo/platform, track fill rate.
Impressions alone don’t guarantee value—pair with viewability and engagement for the full picture.