Types of zone tag

A zone tag is the code chunk that places your ad item on a page. It passes along the ad item information, and usually some extra information, for tracking and display.

Choosing the right type is important because, depending on the situation, your ad item may not show or you may miss some features if the zone isn’t properly configured. See below for a breakdown of characteristics for each different zone tag.

Asynchronous Javascript (Async)

An Asynchronous Javascript tag will reference the incoming ad item and adjust the zone to serve accordingly. For example, if an image-based ad is chosen, it will display inside of an HTML image tag. If a custom HTML ad item is chosen to serve, it will render the ad in an iFrame. Asynchronous Javascript tags are loaded independently of the page contents and do not interfere with the load time of the page.

All new zones are set to use Asynchronous JavaScript by default. It is the recommended that you use this type of zone tag unless you specifically require another type of zone tag to be delivered.
If you are serving an ad to a zone that has a size set to "responsive", you cannot use an Async tag. You must use a Javascript or Image (Basic) tag.

Asynchronous 1.1 (Beta)

The Async Beta tags are used to render ads asynchronously via JavaScript however does not require the document.write method of drawing to the page. Instead, the Async Beta tag will render directly to the placement container DIV.

This is particularly useful in cases like infinite scrolling sites where document.write may cause conflicts with white pages or empty spots.


If you need custom HTML code served inline with the page content (ie. outside of an iFrame), or when a publisher's website causes conflicts with asynchronous tags, you may need to use a JavaScript tag. These tags will serve properly when a zone has its size set as "responsive".

iFrame & iFrame (HTML Only)

Both of these tags will serve almost identically, except the HTML iFrame will not run javascript. It is generally recommended to use these tags ONLY when your publisher has requested them. iFrame tags load content securely and are unable to interact with the page it is displayed on. iFrames also load asynchronously.

iFrames may not serve properly within zones that have a size marked as "responsive".

Image (Basic)

This will serve an HTML image tag wrapped in a hyperlink tag to direct users when they click.

The default behaviour of many modern browsers will be to block any clicks associated with these tags unless authorized in the browser settings or they have a third party cookie installed that allows the click to function.


When using a JSON Ad API tag, an ad request will return a JSON object. The JSON response contains all the base details needed to display an ad item. The JSON response will include the ID of the ad item, the destination for the click and the location of the image, as well as the dimensions and any other settings you’ve set for the ad item and will be rendered/styled according to the HTML/CSS or Javascript included on the page.


These tags are lightweight, easy to use, and are AMP compliant to allow mobile sites to load as quickly as possible. There are two cases where you'll have to modify your AMP tags before they can serve, which you can read about here.

When using an AMP tag, any external resources or assets that are required to display your ad must be served over HTTPS.

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