Glossary
What is Ad refresh?
Also called: refresh, viewable refresh, time-based refresh
Ad refresh loads a new ad into the same slot without reloading the page, on a timer, after an event, or once the current ad has been viewable.
हिंदी में पढ़ेंWith time-based refresh, a slot swaps its ad every set number of seconds. The timer keeps running when the reader switches tabs or scrolls away, so many refreshed ads play to nobody. Viewable refresh waits until the current ad counts as viewable, at least half its pixels on screen for one second, then refreshes only if the slot is still in view and the tab is active. Fewer ads, each worth more.
Google Ad Manager sets rules. Refreshing inventory must be declared under publisher declarations, with its trigger and interval. Time-based and event-triggered refresh on desktop and mobile web need at least 30 seconds between refreshes. Not declaring refresh, or declaring it wrongly, breaks policy, and Google applies buyer restrictions to the requests the declaration covers.
Some buyers will not bid on refreshed slots, and Google says longer intervals are generally more desirable to buyers. Declare only the units that really refresh, with their real interval.
Example
A player stays 3 minutes beside a sticky sidebar ad that refreshes every 30 seconds: 180 ÷ 30 = 6 ads. If the player switched tabs after 1 minute, 4 of those 6 ads played to nobody.
Why it matters to publishers
Refresh can add impressions, but undeclared or careless refresh breaks policy and lowers what buyers pay. Viewable, declared refresh keeps the extra impressions worth something.