Priorities / Waterfall


Priorities determine what sets of ads have precedence over others. For instance, you can set rules so that House Ads (internal promotions) only appear if there's no advertiser to fill the slot.

Priorities work like a waterfall: the Kevel engine will attempt to fill any impressions that aren't captured by the highest priority with the next highest priority, and so on.

They are set at the Channels level. For most clients, this will be the default All Sites Channel.


Priorities are designated by a number: 1 is the highest priority while 100 is the lowest priority.


Default Priorities

Kevel automatically creates three common Priorities for you. You can add up to 97 additional priorities in a given Channel (100 total).

NameWeightSelection Method
Sponsorship 1Lottery
Premium 5Lottery
House 20Lottery

Priority Fields

Below are the fields related to a Priority you'll find in the UI and/or API.

Priority Name Friendly name for the priorityname
Channel The Channel's ID, needed only for the APIChannelId
Weight Determines if ads are prioritized over ads in other priorities (a lower number is prioritized over higher numbers, with 100 last). You can set this to any value not being usedWeight
Selection MethodChoose which selector the ad engines use to select an ad from this priority. Defaults to Lottery (0 in API).SelectionAlgorithm
Optimize Priority for Keyword Serving
Whether its optimized for responding to large number of keyword requests. Cannot be updated after creationIsKeywordOptimized (boolean)
Enable Second Pricing
Auctions only.IsSecondPricing
Floor Price
Auctions only. It's the minimum bid needed to win the slot. Set to 0 if this doesn't matter to you.FloorPrice
Remainder Percentage
Auctions and AdChain Optimized only. Refers to the percentage of impressions that ads with lower eCPMs will receive, which is used to give poor-perfoming ads a "second-chance". Set to 0 if this doesn't matter to you.UI only



This may only be set on creation, and this field cannot be updated. Values include:

0 = Lottery
1 = Auction
2 = Adchain Ordered
3 = Adchain Optimized
4 = Lottery with Outbid


The Remainder Percentage is used to artificially bump up ads that have lower eCPMs. For instance, if you put 5, that means 5% of impressions won't be optimized for max revenue, but will instead be used to give ads that once performed poorly a 2nd chance to get data.

Adding Priority - UI

To add a priority, follow the steps below.

  1. Inventory --> Channels
  2. Click on Priorities, which is to the far right
  3. Click Add a New Priority To This Channel in top left
  4. Fill in the required fields. If creating an Auction priority, there's more info here.
  5. Save
1328 658 574


The Weight cannot be already used by another Priority. Also, once you save, the Selection Method cannot be updated.

Finding a Priority with UI

  1. Go to Inventory --> Channels
  2. Click on Priorities to the right of your Channel (you'll probably be using "All Sites"). You'll find the ID to the right of the name.

Creating a Priority with the API

Use the Create Priority endpoint. The call will look like:

  "Name":"High Priority",
  "SelectionAlgorithm": 1