BidRequest.imp[]

Imp

One ad placement being auctioned. A request can carry several, and each is bid on independently.

Fields

Field	Type	Level	Description
id	string	required	Identifier unique within this bid request.
banner	object	conditional	Required if a banner ad is offered.
video	object	conditional	Required if a video ad is offered.
audio	object	conditional	Required if an audio ad is offered.
native	object	conditional	Required if a native ad is offered.
pmp	object	optional	Private marketplace deals available for this impression.
bidfloor	float	optional	Minimum bid, as a CPM. Defaults to 0.
bidfloorcur	string	optional	Currency of the floor. Defaults to USD.
secure	integer	optional	1 if the impression requires HTTPS assets.
instl	integer	optional	1 if the impression is interstitial or full screen.

Example

{
  "id": "1",
  "bidfloor": 1.50,
  "bidfloorcur": "USD",
  "secure": 1,
  "banner": {
    "format": [{ "w": 300, "h": 250 }, { "w": 336, "h": 280 }],
    "pos": 1
  }
}

What matters in practice

The floor is a CPM in bidfloorcur, not a per-impression price, and the currency is easy to miss — a floor of 2.00 means very different things in USD and JPY. An Imp offering more than one of banner, video and native is offering the exchange a choice, not requiring all of them, which is why a request can look like video inventory and fill with display. If you are debugging why a deal never matches, the pmp object on the specific Imp is where to look rather than anything at the root.

Related objects

Field names, types and requirement levels from the IAB Tech Lab OpenRTB 2.6 specification (2.6-202211), verified 30 July 2026. The practice notes are not spec text.