Bid Modifiers

Set dynamic bids based on targeting criteria for a single Flight.

Bid modifiers allow retailers and other publishers to maximize their ad revenue by facilitating premium bids for advertisers' most valued customers. The functionality allows publishers to sell sponsored listings and other placements with dynamic rates based on targeting criteria. Bid modifiers increase the efficiency of your campaign setup: instead of creating a Flight for each distinct set of targeting criteria and bid, use bid modifiers to configure multiple bids within a single Flight.

Bid modifiers are expressed as multipliers or a fixed price relative to a Flight’s base bid. Here’s a hypothetical example: Big Cashew Co. (a snack food brand) is willing to pay a base bid of $1 per click on its sponsored listing ad shown to shoppers searching for "snacks". Using the bid multiplier functionality, Big Cashew Co. could augment that base bid to say: “if my sponsored listing will appear in the first slot, I’m willing to pay 3 times my base bid (or a $3 CPC) to be more competitive in this premium placement.”

How to configure bid modifiers using the Management API

First specify a base bid for a Flight using the Price field. Then use the BidModifiers field to define bid modifiers as multipliers (eg 1.5x) or a fixed price (eg $5.00) corresponding to matched targeting criteria.

"BidModifiers": [  
    { // When decision request matches keyword 'snacks' AND zone ID 25454, multiply Flight (or Ad if set) price by 2  
        "Match": {"Keyword": "snacks", "Zone": 25454},  
        "Multiplier": 2  
    { // When request matches zone ID 4565, multiply Flight (or Ad if set) price by 1.5  
        "Match": {"Zone": 4565},  
        "Multiplier": 1.5  
    { // When request matches keyword 'healthy snacks', override Flight (or Ad if set) price to 5  
        "Match": {"Keyword": "healthy snacks"},  
        "Price": 5  

When a modifier’s match corresponds to a specific Kevel entity type, the value for that match modifier is the ID of the entity. When an ID is not applicable, the string representation should be used. For keywords, only a single keyword string per match is supported. See the Create Flight API documentation for more details.

How to configure bid modifiers using the Ad Server UI

Coming soon!

Does a Flight need to be targeted to a keyword to have a bid modifier applied to that keyword?

Bid modifiers are separate from Flight targeting. Furthermore, bid modifiers do not need to match Flight targeting—that is, a Flight does not need to target a given keyword in order to set a bid modifier on that keyword and the same applies to all targeting criteria that can be boosted.

Using keywords as an example, if no keywords are set on a Flight, it will be eligible to serve regardless of the keywords passed with the request. This means you can create a Flight without targeting keywords but add bid modifiers to it. If a certain keyword is passed in an ADR (ad decision request) that matches a bid modifier, the bid associated with that modifier will be used instead of the Flight's base price.


A caution on broadly targeted campaigns

When using limited or no specific targeting on Flights, the number of ads considered in decision requests may increase. This can result in increased latency and bid modifiers may not perform as intended—the highest modified bid may not be selected in scenarios where more than 1,000 ads are eligible to fill a single placement. For this reason, Kevel recommends including some keyword or other targeting criteria on all Flights.

How are winning bids seen in the ADR response?

The clearPrice in the decision response will be the final modified bid amount if a multiplier has been applied. Additional details on the targeting that was matched and the bid modifier can be found in the extended explainer response.

What selection methods are compatible with bid modifiers?

Both Lottery and Auction are supported. The Flight must have a non-flat rate type.

How do multiple bid modifiers interact with each other?

When multiple bid modifiers match a single ad decision request, the highest matching bid across all match types will be used.

If I set bids on specific targeting dimensions, then do I also need to set a price on the Flight?

Yes, price continues to be a required field on Flights. The Flight price is treated as a floor price if none of the other targeting criteria apply.

How do bid modifiers interact with Autobid/Target ROAS settings?

Autobid can be used in combination with bid modifiers. The highest bid modifier price is used as the ceiling for bids further adjusted by autobid functionality. This raises the ceiling from the Flight’s price to whatever the highest bid is after any boosting is applied. This is the order of operations used to determine the final bid:

  1. Flight base price (or Ad base price when Ad has a price override set)
  2. Highest matched bid modifier price (#1 * multiplier OR fixed price from multiplier)
  3. Target ROAS adjustment using #2

How are bid modifiers reflected in event logs?

These fields capture information about modified bids in event logs:

  • BidModifier — the bid modifier that was applied (not present if no bid modifier was matched)
  • ModifiedPrice — the price after the bid modifier was applied, but before tROAS (target ROAS) optimization (that's the OptimizedPrice). If no bid modifier was applied this will be the same as the Price.

How many modifiers can be applied to a single Flight?

Up to 100 bid modifiers can be applied to a Flight.

Can bids be modified to go up and down?

Yes. Modifiers can range from 0–10x. Modifiers less than 1 will have the effect of reducing ads’ base bid up to the point of a $0 bid.

Can I choose between setting a fixed price bid or a multiplier?

Yes. Bid modifiers can be expressed as either a multiplier or fixed price amount.

How does this cross over with paying more for a premium position?

Premium positions in Kevel are best represented by a Zone. Zones can be used with bid modifiers—so, if an advertiser is willing to pay more for premium position, they can increase their bid for that Zone.

On what dimensions can an ad be boosted?

Currently bid modifiers can be set on Keywords and Zones with more options rolling out in the future.

Can multipliers be set at the Ad level?

Bid modifiers can be set at the Flight level only. The modifiers are separate from keyword and other targeting set on the Ad or Flight—the two operate independently. If an Ad has a price set, the Ad’s price will be used as the base to be modified (either multiplied or overridden by a fixed price set on a bid modifier).