Google Ads Bidding Strategies: How to Choose One Without Breaking Learning

1. Which bid strategies Google Ads offers today

Google groups bid strategies by goal. Strategies that optimize for conversions or conversion value using machine learning are called Smart Bidding.

Display and video campaigns have their own strategies based on cost per thousand impressions or cost per view, but they are not used for Search or Performance Max. Performance Max only runs on Maximize conversions and Maximize conversion value, with or without a target. If you run Shopping or Performance Max, see our Google Shopping and Performance Max services.

2. What has changed since 2019

If you have read guides to automated bidding written a few years ago, some of their advice no longer applies.

3. What you need before switching on Smart Bidding

3.1. Conversion tracking and primary actions

Smart Bidding optimizes for exactly what you have marked as a conversion. If your primary conversion is a view of the About page or an 80% scroll, the system will learn to bring in people who scroll, not people who buy.

So before you start:

• set as primary only the actions that matter to the business: a lead form, a call above a certain length, a purchase;
• keep micro-conversions (price page views, add to cart) as secondary — they are useful for analysis, not for bid optimization;
• for an online store, pass the order total as the conversion value, otherwise value-based strategies have nothing to work with;
• check that conversions are not duplicated and are recorded correctly. If tracking needs fixing, that is part of our web analytics setup.

3.2. How many conversions you need

Requirements depend on the strategy and campaign type:

• Target CPA has no minimum conversion history and can be switched on even with no conversions. Google calculates the recommended target as your average cost per conversion over the last 30 days;
• Target ROAS needs at least 15 conversions in the past 30 days for Search and Shopping, and 50 in the past 35 days for Demand Gen;
• Maximize conversions and Maximize conversion value have no formal requirements.

Being able to switch a strategy on does not mean it will perform consistently. To evaluate results, Google recommends looking at a 30-day period with at least 30 conversions. If you get only a handful of conversions a month, the system simply has nothing to learn from, and it is better to collect data first.

4. How to choose a strategy

There is no universal "best" strategy. The choice depends on what you know about your conversions and how many you get.

To set a realistic target, you need to know what return on ad spend your margins can support. Our ROAS calculator helps with the numbers.

5. The learning period: how long it lasts and what resets it

After you launch or change a strategy, its status shows "Learning". According to Google’s help documentation, calibration can take up to around 50 conversion events or 3 conversion cycles — that is, three times the average time between a click and a conversion. For a product bought on the day of the click, that is a few days; for B2B with a week-long decision cycle, it is several weeks.

Learning starts again when:

• a strategy is created or reactivated;
• a strategy setting changes, for example the Target CPA;
• campaigns, ad groups or keywords are added to or removed from the strategy.

Results fluctuate during learning, and that is normal. The most common mistake is changing the target or budget every day after a bad day: each change sends the strategy back to the beginning.

If you expect a few unusual days (a sale, a tracking outage), use seasonality adjustments and data exclusions (advanced controls in the bid strategies section). They tell the system what to expect instead of forcing it to relearn.

6. The 17 August 2026 change

Campaigns using Target CPA or Target ROAS that were limited by budget used to overperform their targets. For example, the Target CPA was $40, but the actual cost per conversion was $25. Many advertisers got used to that "bonus".

Since 17 August 2026, these campaigns deliver closer to the stated target. If the target is $40, the system will aim for more conversions at around $40, rather than fewer conversions at $25. The change applies to Search, Shopping, Performance Max, Demand Gen and Display campaigns.

Google does not adjust your targets or budgets automatically. What to do:

• review your campaigns in the Bid Target Adjustment Tool (available since 6 July 2026);
• if you want to keep your current cost per conversion, lower the Target CPA (or raise the Target ROAS) to your actual level;
• if you want to scale, keep the target and increase the budget;
• if you don’t need strict cost control, switch to Maximize conversions without a target.

If your cost per conversion went up after 17 August and you didn’t change the target or budget, this is the most likely reason.

7. Bid adjustments with Smart Bidding

Manual bid adjustments (location, ad schedule, audiences, demographics) mostly don’t apply to Smart Bidding: the system accounts for these signals in every auction. The exceptions:

• with Target CPA you can use device adjustments, but they change the target, not the bid: +20% for mobile means you are willing to pay 20% more per conversion on mobile;
• with Target ROAS, Maximize conversions and Maximize conversion value, only a −100% device adjustment is available, which switches ads off on that device type.

For the same reason, don’t combine Smart Bidding with scripts or third-party rules that change bids. They will fight the automation, and each change they make can send the strategy back into learning.

8. How to move to automated bidding safely

If a campaign performs steadily on Manual CPC or Maximize clicks, don’t switch it to Smart Bidding in one go. It is safer to run a custom experiment:

1. In the Experiments section, create an experiment based on the campaign.
2. In the trial version, change only the bid strategy — nothing else, or you won’t know what caused the result.
3. Split traffic and budget 50/50 between the original and the trial.
4. Don’t judge the result until the learning period is over, and don’t make changes during the test.
5. Compare on the metric the strategy optimizes for — number and cost of conversions, or conversion value — not CTR or average CPC.

If the trial wins, Google lets you apply the changes to the original campaign without relaunching it.

9. Common mistakes

• An unrealistic target. A Target CPA at half your actual cost per conversion, or an inflated Target ROAS, restricts impressions until the campaign barely spends. Start from your actual data for the last month and change the target gradually.
• The wrong primary conversions. Optimizing for micro-conversions produces lots of cheap "conversions" and few sales.
• Frequent changes. Adjusting the target or campaign structure several times a week keeps the strategy from ever leaving learning.
• Judging by the wrong metrics. With Maximize conversions, a rising CPC is not a problem if conversions grow and their cost stays acceptable.
• Too small a budget. If the daily budget is less than the cost of one or two conversions, the strategy gets too little data and performs erratically.
• Auto-applying recommendations without oversight. Some of Google’s recommendations change bid strategies and targets. Review them before they are applied.