Specify constraints

In the Constraints section of the Search Ads 360 bid strategy editor:

1. Enter the default minimum and maximum bids for the Search Ads 360 bid strategy.

   Maximum/minimum bids are the best way of ensuring that bid-strategy bids are always within a range you are comfortable paying.
   After you create the bid strategy, you can also set minimum/maximum bids for specific keywords. Minimum/maximum bids that you set for keywords override the bid strategy's Minimum/maximum settings.

2. Optional. If you selected a CPA goal, you can set additional constraints by clicking More constraints. You can save the bid strategy without setting additional constraints which will allow Search Ads 360 more freedom to optimize against the primary settings.

   If you want to set constraints, choose one of the following additional constraints:

   • Select a position constraint: Combines a position goal with the CPA goal to help your program meet multiple objectives. Search Ads 360 will first ensure that the bid is within the minimum/maximum bid range, then bid to stay within the position range, and finally bid toward the CPA target. Enter a top and a bottom position for keywords. 
     A position constraint doesn't apply to the Google Ads campaigns that are managed by the bid strategy.
   • Select a max CPA constraint. Set a max CPA that is more than the target CPA to allow Search Ads 360 to occasionally bid more to achieve the bid strategy's goal.
3. Click Save bid strategy or optionally click Next to see the advanced configuration options.

Max CPA constraint

We suggest that the value of the max CPA constraint is set to at least 1.5 times the target CPA to allow the Search Ads 360 bid strategy some room to continue to optimize bids for the portfolio. However, this is not a requirement because you may also be able to improve profitability with a lower max CPA.

• max CPA ≥ (1.5 * target CPA)

For example, you sell light fixtures for $40 each. You set your target CPA at $30 because you want to make a $10 profit per fixture after advertising costs.

Your campaign portfolio contains the keywords brand name, lighting fixtures, hanging lights, and bulbs.

To achieve the target CPA of approximately $30 (actual CPA is $31.25), without a max CPA constraint, the bid strategy adjusts bids on the specific keywords as follows:

• $5 for the brand name keyword because it’s at position one. You're probably the only one bidding on your brand name and because it’s at position one, the bids cannot be any higher.
• $60 for lighting fixtures because the lighting fixtures keyword is popular
• $30 for hanging lights
• $30 for bulbs

While the overall bid strategy is profitable, the $60 bid for lighting fixtures is well beyond the $30 target CPA and is unprofitable. To reduce overspending on keywords, you might set the max CPA to $35.