Expandable directions
Expandable directions say which ways an expandable ad may grow beyond its slot, given where the slot sits and what the page allows. OpenRTB 2.x sends them as an array in Banner.expdir, including on companion banners. In OpenRTB 3.0, AdCOM display formats and video placements carry the same list.
Values
| Value | Name | What it means |
|---|---|---|
1 | Left | The ad may expand to the left of its slot. |
2 | Right | The ad may expand to the right of its slot. |
3 | Up | The ad may expand upward. |
4 | Down | The ad may expand downward. |
5 | Full Screen | The ad may expand to fill the whole screen. |
6 | Resize or minimize | The ad may shrink below its initial size, for example collapsing to a smaller bar. |
Fields that use this list
How to use it
List every direction the slot can expand in, and leave out directions that would cover navigation or run off the screen. A slot at the right edge of a page should not offer 2 (Right). Expansion also needs a frame the creative can escape, so check Banner.topframe and the API frameworks in Banner.api, such as MRAID in apps, before advertising expansion at all. Values 1 to 4 date from OpenRTB 2.0, 5 was added in 2.2, and 6 comes from AdCOM. Sellers that do not want expandables should block the expandable creative attributes (3, 4 and 5) in battr instead of sending an empty expdir.
Common mistakes
- Sending
expdiras a single integer. It is an array. - Offering expansion from a cross-domain iframe that cannot resize, which leads to broken creatives.
- Relying on 6 with buyers built against OpenRTB 2.5 or earlier, where the list stops at 5.
Validation
On OpenRTB 2.6 snapshots, RTBlint reports a value outside this list as openrtb.value.invalid. Paste a request into the tester to check the values you send.
Related lists
All lists are on the enumerated lists index.