Imp.dt

Estimated time the impression will be delivered, as Unix epoch milliseconds in a float. Added in OpenRTB 2.6-202211, mainly for digital out-of-home screens that schedule plays ahead of time.

CurrentfloatOptionalSince 2.6-202211

Field facts

Path: imp.dt
Object: Imp
Type: float
Requirement: Optional
Added: OpenRTB 2.6-202211
Spec section: 3.2.4

How it is used

Buyers use it to check that the play falls inside a campaign's flight and dayparting, since a DOOH auction can run well before the ad appears.

Example

Where the field sits in a payload, with everything else left out:

{
  "id": "req-1",
  "imp": [
    {
      "dt": 1794074400000
    }
  ]
}

Common mistakes

Sending seconds since the epoch instead of milliseconds dates the impression to January 1970.

Version history

Added in OpenRTB 2.6-202211, and present in the latest snapshot. The table shows how each version's spec text types the field.

Versions	Type in the spec	Required	Deprecated
2.6-202211 to 2.6-202606	float	No	No

Related fields

Other Imp fields

For a walkthrough of the whole object, read Bid request anatomy.