Interstitials are full-screen display ads that appear between pageviews. Readers can close them immediately, and there is no countdown to view them.

They are frequently capped, which means not everyone will see them, and they will only appear if a reader clicks on an internal or external link, or when a user clicks on the browser's navigation bar.

Here is an example:

Interstitial ads are highly viewable and command the reader's attention. Advertisers will pay top dollar for them. In testing, we've seen an average increase in desktop RPM of 7.7%.

Google AdExchange renders interstitial creatives to "match Google search standards". Since they will not appear on the first screenview and only after a link is clicked, they will have no impact on SEO.

Like most things, it really does depend on the site. We offer these because they can boost performance, and we want you to have plenty of options to customize your ad experience. Whether or not they are a good fit for your site depends on your goals.

How much desktop traffic does your site get?

These units can be disruptive to the reader experience, so if you're not getting much desktop traffic, you likely won't make enough to justify potentially alienating readers with a full-page display ad.

What is the right balance between revenue and user experience for your site?

Desktop interstitials can give a nice boost to your desktop RPM, but it comes at a price. Unexpected full-page ads between pageviews aren't the best user experience, and that's something to consider before enabling.

Both mobile and desktop interstitials are in the Optional Ad Unit section of your dashboard. Settings > Ad Settings > Optional Ad Units

It will be in the Ad Unit breakdown section on the first page of the dashboard.

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