Recommended fields to send for outstream video inventory in OpenRTB bid requests

Media Owners
Last Updated: February 16, 2026•

For better monetization of your outstream video inventory, we strongly recommend that you pass as many fields as possible to describe your inventory. Outstream inventory could include accompanying content, interstitial, or no content/standalone content. We have included a list of recommended fields that you can pass in the bid request Video object.

Recommended fieldsTypeDescription

plcmt

Integer; optional

The video's placement type according to the IAB Digital Video Guidelines. For more information about the recommended plcmt values, see Sending the plcmt field in OpenRTB bid requests. You must also specify the playback method for the placement in the playbackmethod field.

Note: If you send both the plcmt and placement fields, Index will use the values in the plcmt field in the bid request.

mimes

String array; required

List of supported content MIME types, where we recommend that you send the following:

  • video/mp4

  • application/javascript

  • video/webm

  • If your video ad unit supports VPAID and you want to receive VPAID ads, make sure to specify application/javascript as the a MIME type. For VPAID, you must also specify the below api framework in the api field.

api

Integer array; optional

For VPAID ads, you must specify the supported api framework, where we recommend that you send one of the following:

  • 1 = VPAID 1.0

  • 2 = VPAID 2.0

If your video ad unit supports OMID 1.0, which is Open Measurement for Web Video​, we recommend that you send the following:

  • 7 = OMID 1.0

minduration

Integer; required

The minimum video ad duration in seconds. We recommend that you decrease the duration by one second to allow for any VAST encoding nuances​.

Example: For a minimum 6 seconds video ad duration, you can specify the minduration as 5 seconds.

maxduration

Integer; required

The maximum video ad duration in seconds. We recommend that you increase the duration by one second to allow for any VAST encoding nuances​.

Example: For a 30 seconds maximum video ad duration, you can specify the maxduration as 31 seconds.

protocols

Integer array; required

An array of supported video protocols, where we recommend that you send the following:

  • 2 = VAST 2.0

  • 3 = VAST 3.0

  • 5 = VAST 2.0 Wrapper

  • 6 = VAST 3.0 Wrapper

  • 7 = VAST 4.0
  • 8 = VAST 4.0 Wrapper
  • 11 = VAST 4.1
  • 12 = VAST 4.1 Wrapper
  • 13 = VAST 4.2
  • 14 = VAST 4.2 Wrapper

minbitrate

Integer; optional

The minimum bit rate in Kbps. We recommend a minimum bit rate of 300 Kbps.

maxbitrate

Integer; optional

The maximum bit rate in Kbps. We recommend a maximum bit rate of 30,000 Kbps.

playbackmethod

Integer array; optional

A list of allowed playback methods, where we recommend that you send the following:

  • 6 = player loads on entering viewport with sound off.

This also provides a better user experience.

delivery

Integer array; optional

A list of supported delivery methods, where we recommend that you send one or more of the following:

  • 1 = streaming

  • 2 = progressive

linearity

Integer; optional

Specifies whether the ad impression is linear or non-linear, where we recommend that you send the following:

  • 1 = linear

Sending this makes sure that the response you receive is a VAST message containing video assets.​

pos

Integer; optional

Specifies the position of the ad as a relative measure of visibility or prominence, where:

  • 0 = unknown
  • 1 = above the fold (default)
  • 2 = deprecated (resolution dependent)
  • 3 = below the fold
  • 4 = header
  • 5 = footer
  • 6 = sidebar
  • 7 = full-screen