Best Practices for RTB buyers

Last updated on March 5, 2018

In addition to the information that we provide on using the OpenRTB API and macros, we share some best practices for RTBReal-time bidding, auctioning online inventory within an ad exchange. Buyers bid for the impression based on the value of the user, whereas the seller sets pricing floors and awards the impression to the highest bidder. The auction process takes place in milliseconds, which is why the process is referred to as “real-time.” buyers.

Pass a CRID

OpenX requires you to pass a CreativeThe media asset associated with an ad, such as an image or video file. ID (CRID) in the field for each unique creative, including variations in:

  • Size
  • Appearance (look or behavior)
  • Landing page URL
  • File format

You must place the unique CRID identifier assigned by the buyerA company that pays a demand partner to purchase ad inventory on OpenX Ad Exchange.’s system in the CRID field of your bid responses. Each CRID you return must consistently be associated with the same creative, both at serve time and if the associated ad code is subsequently called by OpenX's audit system. The identifier CRID string that the buyer creates may be any valid UTF8 string of 64 bytes or less.

Whitelist the following IP address:

For ad qualitySettings that control the types of ads that can display on your inventory. scanning, OpenX uses the above IP address. OpenX regularly scans creatives to ensure they adhere to our ad quality standards.

Note: The scanning system will substitute whichever price macro you use ({winning_price}, {WINNING_PRICE}, ${AUCTION_PRICE:OXCRYPT}, etc.) with AUDIT for the price value. For example, &pp=${AUCTION_PRICE:OXCRYPT}&xyz=... becomes &pp=AUDIT&xyz=.... You are not charged for these scans, so please build in logic to not count impressions that result in “AUDIT” as valid impressions. If not, this may lead to impressionA single display of an ad on a web page, mobile app, or other delivery medium. For deals, impression is a metric to relay the total number of ads that have served. See also billable impression, forecasted impressions. and spend discrepancies.

Populate the adomain value

The adomain value must always be present and should be the actual landing page of the ad.

Ensure all ads are non-rotating

Please do not submit ads that rotate to different brandsA name that represents the product or service being advertised, such as Tide. and/or media types. Rotating creatives will be discarded as an ad quality violation.