What is Ad Impressions?
The number of times an advertisement is displayed to users.
Ad Impressions represent the total count of how many times an advertisement is served and potentially viewed by users. Each time an ad loads and appears on a user's screen, it counts as one impression, regardless of whether the user actually looks at or interacts with the ad.
Why It Matters
Ad impressions are the foundation of digital advertising measurement and revenue calculation. For publishers, impressions directly correlate with ad revenue potential through CPM (Cost Per Mille) pricing models. For advertisers, impression data helps measure campaign reach and brand exposure. Understanding impression metrics is crucial for optimizing ad placement, frequency capping, and overall monetization strategy.
How to Calculate
Ad Impressions are typically calculated as: Total Impressions = Sum of all ad serves across all placements and time periods. For impression-based revenue: Revenue = (Impressions ÷ 1000) × CPM Rate. Fill Rate = (Filled Impressions ÷ Total Ad Requests) × 100.
Industry Benchmarks
| Category | Average | Good Performance |
|---|---|---|
| Mobile Gaming | 90-95% fill rate | 98%+ fill rate |
| Social Apps | 85-92% fill rate | 95%+ fill rate |
| Utility Apps | 80-88% fill rate | 90%+ fill rate |
Best Practices
Monitor fill rates to ensure ad inventory is being monetized effectively. Implement frequency capping to prevent ad fatigue and maintain user experience. Use multiple ad networks through mediation to maximize fill rates. Track viewability metrics alongside impressions to ensure ads are actually seen. Optimize ad placement for both user experience and impression opportunities.
Examples
A mobile game showing banner ads at the bottom of the screen generates 1 impression each time a player starts a level. An interstitial ad shown between game rounds counts as 1 impression per display. A rewarded video ad that plays completely generates 1 impression regardless of whether the user claims the reward.
Notes
Not all impressions are equal - viewable impressions (where the ad is actually visible on screen) are more valuable than non-viewable ones. Different ad formats have different impression counting standards. Some networks count impressions when the ad request is made, while others count when the ad is actually displayed.