Create an ad unit

Define the basic unit of inventory

An ad unit is the basic unit of inventory in Google Ad Manager. You can group one or more ad slots as an ad unit, which is one block of inventory that can be targeted by line items.

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How to create an ad unit

  1. Sign in to Google Ad Manager.
  2. Click Inventory and then Ad units.
  3. Choose an ad unit under which you'd like to create a new ad unit. Or, do not choose any ad unit to create a top-level ad unit.
  4. Click New ad unit.
    • Select One level below... to create an ad unit below a selected ad unit.
    • Select Current level to create an ad unit at the same hierarchy level as a selected ad unit.

    Google Ad Manager publishers can add 2 levels of ad unit hierarchy. Google Ad Manager 360 networks can create up to 5 levels of ad unit hierarchy.

  5. Enter a Code, which is used to identify the ad unit in the associated ad tag. Once created, the ad unit code cannot be edited so define a code that is easy to identify. For example, News_International_BoxATF or Leaderboard_BTF.
    Ad unit codes can be up to 100 characters in length and are not case-sensitive.

    Only letters, numbers, underscores, hyphens, periods, asterisks, forward slashes, backslashes, exclamations, left angle brackets, right angle brackets, colons and parentheses are allowed.

    For a given ad unit level, each code must be unique; you can't reuse codes you've used before on the same ad unit level. You can reuse codes if they occur on a different ad unit hierarchy. For example, you can reuse home if it occurs in a different path of the hierarchy, such as mysite/economy/home and mysite/weather/home

  6. Enter a Name for the ad unit, used in targeting and reports. You can change the name at any time. As with the code, publishers typically use naming conventions that give information about the ad unit's location.
  7. Enter a description for the ad unit, if needed, up to 4,000 characters in length.
  8. Set the Sizes to be associated with this ad unit to help Google Ad Manager filter the list of ad units for traffickers. This list is optional and will not affect ad serving.

    Want to add a new size to your network?

    Create a new ad unit and add the new size, or add the new size to the list of sizes assigned to an existing ad unit. As long as a size is defined in at least one ad unit or line item, it can be used elsewhere in your network.

    • Select Fixed size to define a list of sizes for creatives you expect this ad unit to serve. Include the Out-of-page size for creatives that don’t fit in a traditional banner space or browser window, including pop-ups, floating line items, and interstitials.
    • Select Smart Banner if the ad unit is for a mobile app and you want the ad unit to have a fixed height but fill the width of the screen. Learn more
  9. (Not applicable to Ad Exchange tags) Define a target window, which sets the target attribute of the ad's click-through link to tell the browser where to open the ad's landing page.
    • _top: The landing page will load in the full body of the window, breaking out of any framesets.
    • _blank: The landing page will open in a new, unnamed window.
    This selection follows the default target window set in the Inventory section's "Network settings". If the ad unit is in a mobile app, the target window is ignored. For Android and iOS apps, ads load in a new, unnamed browser window.
  10. (Not applicable to Ad Exchange tags) Add optional features and settings to the ad unit as needed.
    • Placements: Click include next to one or more placement names to associate your new ad unit.
    • Special ad unit: Requires traffickers to explicitly target the ad unit in order for line items to serve. Learn more

       Only available in Google Ad Manager 360.

    • Ad unit frequency caps: Click Add a labeling rule to limit the number of impressions displayed to users for creatives that share the defined labels. Learn more
    • Refresh rate: For mobile app inventory, set a refresh rate to determine how often a new ad impression is generated. If you select Refresh rate in seconds, Google Ad Manager auto-populates a value of 60, which you can change to any value between 30 and 120 seconds. Learn more
    • Labels: Add labels to the ad unit so that creative wrappers can be applied when creatives are served to the ad unit. Learn more
    • Teams: If your network uses Teams, associate this ad unit to restrict access.
  11. Click Save.

Inventory forecasts for new ad units
Forecasting numbers will be smaller than expected until enough time has passed since new ad units have received traffic.
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