Smart Bidding is Google’s family of bid strategies that optimize for conversions or conversion value, setting a fresh bid for each auction using signals such as device, location, time, audience lists and the query. The main strategies are Maximize conversions, Maximize conversion value, and their optional targets, target CPA and target ROAS. Its quality depends heavily on the conversion data you give it.
The strategies
- Maximize conversions: get as many conversions as possible within the budget.
- Maximize conversions with a target CPA: aim for an average cost per conversion.
- Maximize conversion value: get as much conversion value as possible within the budget.
- Maximize conversion value with a target ROAS: aim for a ratio of value to spend.
What it needs
Smart Bidding learns from conversions, so it works best when it sees enough of them, when they arrive reasonably quickly, and when they reflect real business value. B2B SaaS accounts often have too few demos for the model to learn well, or a conversion action that rewards junk leads.
Common fixes are consolidating campaigns, importing qualified stages from the CRM with values, and avoiding big swings in targets, which can restart the learning period. Enhanced CPC, a semi-automated option, was retired for most campaign types in 2024 and 2025.
Watching it
Automation does not remove the need for oversight. Watch search terms, conversion quality and spend by campaign. If conversions rise while pipeline stays flat, the model may be optimizing toward the wrong thing.
Example
Switching the conversion it learns from
Hypothetical company Gorsefield uses Maximize conversions on all form fills and gets a rising number of leads that sales rejects. It makes imported sales-qualified leads the primary conversion, demotes raw form fills to secondary, and accepts a few weeks of higher cost per conversion while the model relearns.
Common mistakes
Changing targets every few days
Frequent large changes keep the strategy in a learning state. Make moderate adjustments and give each one time.
Questions
Google gives guidance in its documentation and recommendations, and it has changed over time. In general, more conversions within the conversion window give the model more to learn from.
