BidRequest.wlangb

An allow list of creative languages as IETF BCP 47 tags, which can name regional and script variants such as pt-BR or zh-Hant. Added in 2.6; send it instead of BidRequest.wlang, not alongside it.

Currentstring arrayOptionalSince 2.6-202204

Field facts

Path: wlangb
Object: BidRequest
Type: string array
Requirement: Optional
Added: OpenRTB 2.6-202204
Spec section: 3.2.1

How it is used

BCP 47 lets a publisher separate variants that share a two-letter code, such as Simplified and Traditional Chinese. Bidders compare the list with Bid.langb or Bid.language on the creative they plan to return.

Example

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

{
  "id": "req-1",
  "wlangb": [
    "en-US",
    "es-419"
  ]
}

Common mistakes

Sending both wlang and wlangb.
Underscores, as in en_US. BCP 47 separates subtags with hyphens.

Version history

Added in OpenRTB 2.6-202204, 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
2.6-202204	Added in the first 2.6 release, published without a structured text archive; the 2.6-202210 republication is the first tagged text.
2.6-202210 to 2.6-202606	string array	No	No

Related fields

Other BidRequest fields

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