Eligible ad slots can be expanded up to the container width. Experiments indicate that allowing ad slots to accommodate larger creatives typically leads to better performance compared to ad slots restricted to narrower than available widths. This improvement is due to increased demand eligibility and click-through rates.
Ad slots eligible for expansion
Ad slot expansion for desktop and tablet currently applies to backfill display and non-in-stream video ad slots. Not all ad slots are currently capable of expansion, though we’re working to increase eligibility.
How ad expansion for desktop and tablet works
It's important to understand that the "container width” is the box containing the ad slot, whose size is defined by the publisher’s web development team.
You should avoid requesting a size that is bigger than the container dimension. Ad slot expansion does not automatically resize when bigger creatives are returned.
Ad slots may expand up to the width of the container, while the height may increase proportionally when appropriate to preserve the aspect ratio. However, ad slots may not always fill to the full container width. There may be times when ad slots:
- Expand by width but not height.
- Don’t expand at all.
Control ad expansion for desktop and tablet
Ad slot expansion is enabled by default. You can turn it off in network settings, though we recommend keeping it enabled for optimal performance.
- Sign in to Google Ad Manager.
- Click Inventory, then Inventory rules, and then Size settings.
- Next to “Targeting,” choose which inventory to include or exclude from the rule.
- Control which size settings are enabled on the selected inventory.
- Click Save.
Unified pricing rules and ad slot expansion
By default, Unified pricing rules apply to all sizes. However, if you have specified pricing for individual sizes and an ad slot is expanded to a size that wasn’t requested, the requested sizes will still be considered in selecting the rules that get applied. The requested size that is closest to the expanded size will be used for selecting the rule.
Example
You've requested an ad with the size 320x480 or 300x250, the ad served is 412x494, and you have three pricing rules.
- The first pricing rule targets ad size 320x480 and 1x1.
- The second rule targets size 400x500.
- The third rule targets size 300x250.
Only the first pricing rule will apply because it has the requested size that is closest to the size of the ad served.
