Ad Fill Rate
Percentage of available advertising inventory that is sold and filled with paying advertisers
What is Ad Fill Rate?
Ad fill rate is the percentage of available advertising slots that were filled with an ad. It shows how much of a publisher's ad space is being monetised.
Unfilled impressions earn nothing, so a low fill rate points to lost revenue from weak demand or poor targeting.
How this KPI is measured
- Function
- Sales
- Sub-function
- Ad Revenue
- Industry
- Media & Entertainment
- Type
- Lagging
- Impact
- Revenue
- Unit
- %
- Measurement frequency
- Monthly
- Formula
- (Filled ad impressions / Total available ad impressions) × 100
How to calculate it
Divide filled ad impressions by total available ad impressions, and multiply by 100.
For example, if 10,000,000 impressions were available and 8,500,000 were filled, the fill rate is 85%.
Look at the rate by placement, format and audience, and consider the price earned as well, since filling slots cheaply may not be best.
Where it is used
Finding lost revenue
Spot unsold inventory.
Improving demand
Add advertising partners and networks.
Optimising placements
Adjust layouts that attract fewer advertisers.
How to improve it
Tips and common mistakes
- A 100% fill rate at a very low price is not the goal.
- Keep user experience in mind. Too many ads reduce engagement.
- Compare with the revenue per thousand impressions.
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