Bid Cap is one of Facebook’s bid strategy options, which guides Meta on how to bid in the ad auction. A Bid Cap sets a maximum bid across auctions, rather than allow them to bid dynamically.
When you enter an ad into the auction, Meta will bid for you. But in some cases, it may benefit you to adjust the bidding strategy to get better results. Options include Highest Volume, Cost Per Result Goal, Highest Value, ROAS Goal, and Bid Cap.
When using the Highest Volume bid strategy, advertisers can choose to set a Cost Per Result Goal. This allows to establish how much you’re willing to pay for the optimized action. It’s not a hard cap, but a goal the algorithm will consider.
The default bid strategy when using the Purchases objective and “Maximize value of conversions” performance goal. Instead of trying to get you the most conversions within your budget, Meta’s focus will be on getting you the highest purchase value.
The default bid strategy for most objectives. Meta will attempt to get you the highest volume of optimized actions within your budget. No concern will be given to value, ROAS, or cost per action.