As a publisher, you know the secret for higher ad revenue: increasing the demand for your ad spaces. Doubleclick has further pushed this opportunity by offering custom sizes and flexible inventory sizes. This relieves the limits on ad slot sizes.
To make it clear: Inventory size refers to the ad slot size. Creative size is the size of the actual ad creative that fills the ad slot. You can use both custom-sized ads or flexible-sized ads or just one of them, in order to up your earning potential. Here are their distinct features:
Allow publishers to send ad requests for any size; and Ad Exchange buyers can bid with creatives of any size, as well. Custom sizes expand to accommodate both inventory and creative sizes outside the “standard sizes”.
For example, an 800×250 is a non-standard ad size but both Adx buyers and sellers can now serve those types of ads because Custom Sizes expand to accommodate it.
Google states: “ You can make custom-size ad requests through DoubleClick for Publishers (DFP) dynamic allocation or through an ad tag. Also, you can use custom sizes in rules, deals, and reporting the same way you use the standard sizes.” Here’s How:
Related Read: DFP For Beginners
Help you make a rule specifying a set of creative sizes to match a specific inventory of yours. It is ideal that you set your maximum flex ad size using the largest available Adx size within each placement.
For example: if an ad unit has a flex 320×50, 320×100 and 300×250, rather than running three separate line items or one line item with three creatives for each size, you should only run a 300×250 because it’s the largest and can run the most ad sizes that are the same size or smaller. This enables more ads to compete for your inventory as the size limit is eased out.
Publishers have to take note though, that they may see smaller creatives appearing in larger inventory ad sizes (ad slots).
Here are some pointers from Doubleclick Ad Exchange about the use of Flexible Sizes:
Related Read: AdSense Offers Responsive Ad Units
Google states that:
“Custom Sizes and Flexible Sizes can be used alone or together. For example, flexible sizes are a great way to open up the number of creative sizes an ad slot will accept, regardless of whether it’s a custom or standard size. If you use a custom size, we recommend also utilizing the power of flexible sizes to increase the initial fill rate for the new-size inventory.”