What Are Impressions?

In the context of advertising, an "impression" represents a display or exposure of an advertisement to a user. Every time an ad is actually loaded onto a page and has the opportunity to be seen by a visitor, it is counted as an impression.

Impressions are a key metric in measuring the exposure of an online advertising campaign. They indicate how many times an ad has been displayed, regardless of whether it was clicked on or not: while an impression signifies that an ad has been displayed, a click denotes that a user has actually interacted with that ad. The ratio of the number of clicks to the number of impressions is known as the click-through rate (CTR).