What is an Ad Impression?

The official definition of an ad impression is when an advertisement loads from a server to a browser. For an ad impression to take place, the correct content for the ad, which is typically stored underneath a visual ad and is invisible to the naked eye, must be fully loaded to a users web browser from its host server.

There are multiple reasons why an online advertisement might NOT register an impression.

  • Ad Bots
    Ad bots scour the internet for opportunities to hack websites or glean user information.  When an ad bot appears on a website instead of a user, they count as a false impression although they might appear as legitimate website traffic.
  • Broken Links
    Errors are not uncommon on the internet, and likewise, it is not unusual for an error to occur with an online advertisement. Broken links do not equate to bot traffic or fraud; they mean communication did not happen as intended between a browser and a server. If a broken link is present, however, no impression is made.
  • Fraud
    Some scammers create online advertisements and create false impressions on accounts to get paid.  Actions such as this are fraudulent, and businesses that intend to purchase online advertisements based upon ad impressions should be aware that such scams exist.

Why are ad impressions important?

Typically, online advertisements are priced and sold according to the possibility that they will receive impressions.  This calculation is known as performance-based advertising.

Online businesses that choose to purchase advertisements based on impressions need to be familiar with these terms:

Cost per Impression

The price for many online advertisements is calculated based upon a cost per impression.  When a business purchases advertisements based upon cost per impression, they receive a charge each time their advertisement fully loads from its hosting server.  Typically, cost per impression advertisement packages requires a minimum or a maximum number of impressions a business can purchase at one time.

Cost (Pay) per Click

Cost (Pay) per click marketing is an online advertising campaign where advertisers pay when one of their ads is clicked on by a consumer. This form of marketing can be cost effective as the advertiser does not have to pay until a consumer clicks on the link. Cost per click advertising is often combined with cost per impression advertising or offered as an alternative.

Cost per Order

Cost per order or per conversion is how businesses calculate the cost or value of their online advertising package.  Cost per order includes the price of cost per impression and cost per click and determines the rate required to acquire a potential customer.  Many businesses base their online advertising budgets based on cost per order.


Understanding ad impressions, the cost involved, and elements that factor into an official count helps a business to make better decisions when it comes to online advertising.

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