Custom ad units and sizes

An ad unit is a named creative size — Leaderboard (728x90), Medium Rectangle (300x250). The catalogue under Admin → Creatives & tags → Custom ad units & sizes is what every size dropdown in the product is drawn from: the placement’s Size combo, the creative’s Ad unit combo, the header-bidding slot editor and the auto-placement template. Each unit says which placement types it fits and whether the supply side, the demand side or both may pick it.

Example. A publisher wants a 970×250 billboard above the fold. Add a unit Billboard (970x250), width 970, height 250, Site Placement ticked, Inventory side and Campaigns side on. From the next page load the network manager picks Billboard (970x250) on a new site placement, and the advertiser’s creative form offers it under Ad unit; a creative uploaded at that size matches the placement.

Typical scenarios

You want	Set	Result
A new standard size on both sides	Title Billboard (970x250), 970 × 250, Site Placement, Inventory side + Campaigns side	Offered on site placements and on creatives
A size publishers may sell but advertisers should not pick directly	Campaigns side off	Placements offer it; the creative Ad unit combo does not
A mobile-only size	Tick Mobile Site Placement only	Never offered on a desktop Site Placement
A “whatever fits” slot on video players	A unit with Custom on and 0 × 0, Video Placement ticked (the shipped Custom Video Player)	The placement form shows manual width/height inputs instead
Retire a size nobody should pick	Untick every placement type (or delete it, if no live placement uses it)	A unit with no placement type appears nowhere

Step by step

1. Open Admin → Creatives & tags → Custom ad units & sizes. The grid shows Title, Placement types, Width, Height, Custom, Inventory side and Campaigns side for every unit, the shipped catalogue included.

   

2. Click Add (or tick a row and Edit). Type the Title — the convention in the shipped catalogue is Name (WxH) — and the Width and Height in pixels.

3. Tick the Placement types the size fits, and leave Inventory side and Campaigns side ticked unless one side should not see it.

4. Save. The toast reads Done. The size is offered from the next page load wherever its placement types and sides say.

5. To remove a unit, tick it and click Delete. A size used by any non-deleted placement is refused — see the caveats.

Caveats and exceptions

• Who can do this. An admin role with the Custom Ad Units & Sizes Admin UI permission. Opening the URL without it shows Record not found. Network managers, publishers and advertisers never see this page; they meet the result in their size dropdowns.

• Where a size shows up is decided entirely here. Placement types plus the two side flags are the whole answer — there is no per-role tick-list that also has to be satisfied before a new size appears:

  Where	Needs
  Placement Size combo	matching placement type + Inventory side
  Creative Ad unit combo, advertiser grid size filter	matching placement type + Campaigns side
  Header-bidding slot editor	Inventory side + a non-zero width and height, and a placement type that matches the slot’s kind
  Template test page	Inventory side — and only for a Site-placement template; the page offers no size for any other type
  Auto placements Size combo	matching placement type, and the unit must not be Custom

• A size with no placement type ticked appears nowhere at all. The lookup is driven entirely by the placement-type set, so an empty set matches no query.

• Custom units are size-less placeholders. Picking one on a placement or a creative reveals manual width/height inputs rather than fixing the size. Each placement type conventionally has one — Custom, Custom Mobile, Custom Video Player, Custom Application. A custom unit is deliberately excluded from the Auto placements Size combo — a size-less unit cannot be an auto-placement template, even though the same unit is selectable on a hand-made placement of that type. (The header-bidding slot editor drops it too, for the different reason that it requires a non-zero width and height.)

• Deleting a size used by any non-deleted placement is refused with Cannot delete size, it is used by not deleted placements. The check looks at placements only — a size used solely by creatives deletes without a warning, and those creatives lose their ad unit.

• Any size (deprecated) is a legacy flag, not a convenience. It describes a placement slot, so every creative-side list — the creative form, the mass banner upload and the REST banner ad-unit list — drops units carrying it, whatever their Campaigns side box says. A creative given such a unit would be stored at 0×0 and match no placement. Do not set it on new units. The Auto placements size list is the one exception: it keeps the Any Size unit — see Other admin tools.

Not working?

Symptom	Likely cause	Check
The new size is not in the placement’s Size combo	The placement’s type is not ticked, or Inventory side is off	Edit the unit → Placement types, Inventory side
The new size is not in the creative’s Ad unit combo	Campaigns side is off, the placement type does not match, or Any size (deprecated) is on	Edit the unit
The size is missing from the header-bidding slot editor	Width or height is 0, or the unit is Custom	Give it real dimensions
The size is missing from Auto placements	The unit is Custom	Pick a sized unit for the template
Delete is refused	A non-deleted placement still uses the size	Change those placements’ size first; a creative-only use does not block
A creative shows 0×0	It was given a unit with Any size (deprecated)	Re-pick a real unit on the creative

Reference

Field	What it does
Title	The label shown in every size dropdown. Required, max 255 characters. Convention in the shipped catalogue is Name (WxH), e.g. Leaderboard (728x90).
Width / Height	Pixel dimensions, 0–3000 each. Left at 0 for a Custom unit, whose dimensions are typed per placement instead.
Custom	Marks the unit as a size-less placeholder. Picking it on a placement or a creative reveals manual width/height inputs rather than fixing the size.
Any size (deprecated)	Legacy wildcard flag. Do not set it on new units. Creative-side lists skip units carrying it — see the caveats.
Inventory side	Offer this size on the supply side — placements, header-bidding slots, template test pages. Ticked on a new unit.
Campaigns side	Offer this size on the demand side — creative Ad unit combos and the advertiser grid filters. Ticked on a new unit.
Placement types	Eight checkboxes: Site Placement, Mobile Site Placement, Non-standard Placement, Video Placement, Application Placement, Email Placement, Click-through Placement and Native Placement. A size is only offered on a placement of a ticked type.

Permission	Lets you
Custom Ad Units & Sizes (Admin UI)	Open the page, add, edit and delete units.

Over the API, GET /rest-api/ad-units.do lists the ad units of each placement type — the same catalogue the placement and banner endpoints size an entity with; see Creative ad specs for the shipped catalogue.

Related

• Other admin tools — the other small admin pages and the shared routine
• Create a placement — placement types and sizes
• Creative ad specs — where the ad units in the Size combo come from
• Header bidding — the slot editor