What Is Smart Bidding in Google Ads?

Google's own help page names exactly four: Target CPA, Target ROAS, Maximize conversions, and Maximize conversion value. Everything else in the bidding menu is either manual or not Smart Bidding.

Target CPA chases a cost per conversion you name. Target ROAS chases a return on ad spend you name. Maximize conversions chases the most conversions your budget can buy. Maximize conversion value chases the biggest total revenue your budget can buy.

For an ecom store the split is simple. If you care about revenue per dollar spent, you are in the ROAS pair. If you care about volume and you have the margin to absorb it, you are in the conversions pair. Picking the wrong pair is the most common bidding mistake there is, and it looks like a settings problem rather than a strategy one.

Google's definition: "Maximize conversion value bidding is a Smart Bidding strategy that helps you get the most conversion value from your budget." It may bid higher for an auction that looks likely to bring a bigger order.

Two rules come with it. First, you need conversion tracking that sends real transaction values. If every sale reports the same value, the strategy has nothing to tell a $40 order from a $400 one. Second, it tries to spend your whole daily budget. Google itself tells you to check your budget before you switch, because a campaign that was underspending can start spending all of it.

You can add an optional target ROAS. Google says that with a target set, Maximize conversion value behaves like a Target ROAS strategy. So the real choice is not two strategies, it is whether you name a return or leave it open.

Maximize conversions counts orders. Maximize conversion value counts money. Google puts it this way: Maximize conversions tries to get the most conversions, whatever their value, while Maximize conversion value tries to get the most value for the budget.

For a store with one product at one price, the two land close together. For a store where orders range from $20 to $500, they behave very differently. Maximize conversions will happily buy ten small orders. Maximize conversion value will chase the big basket. Pick the one that matches what actually pays your bills.

Google's own one-liners: Target CPA sets bids to get as many conversions as possible at the cost per action you set. Target ROAS sets bids to get as much conversion value as possible at the return on ad spend you set.

The number you type is the bid decision now. Set it too tight and the campaign starves. Set it too loose and it buys volume you cannot afford. Set it from your own margin maths, not from what the account happened to do last month.

Google describes Smart Bidding as using "Google AI to optimize for conversions or conversion value in every auction, a feature known as 'auction-time bidding'". Read that literally. There is no single bid sitting on your keyword any more. There is a fresh bid, worked out for each search, at the moment it happens.

The signals Google names are why it can do that. Device type. Location, "down to the city". Time, "based on someone's local time of day and day of week in their time zone". On-site behaviour, including "number of pages viewed, value of products browsed". And the search itself, "based on the text of the query that triggered the ad".

That is a lot of context you could never price by hand, which is why manual bidding lost. It is also why Smart Bidding on a clean account with good conversion tracking usually beats a person, and costs nothing extra.

Manual CPC still exists. You set the bid yourself, per keyword or ad group. It suits a tiny account with too few conversions for Smart Bidding to learn from, and almost nothing else.

Enhanced CPC is gone for most campaigns. Google says that from the week of March 31, 2025, Enhanced CPC is no longer available for Search and Display campaigns, and campaigns that were not moved now run on Manual CPC. If an old campaign still says ECPC in your notes, check what it really runs on today.

A bid strategy shows "Learning" after three kinds of change: a new or restarted strategy, a changed setting, or campaigns, ad groups or keywords added to or removed from it. Google says it can take a few conversion cycles, one to two typically, for the strategy to settle. How long that is depends on how many conversions you get and how long your buyers take to decide.

Changing a target CPA or target ROAS is not on that list. Google says a new target does not start learning and does not wipe what Smart Bidding already knows.

The practical rule is to leave it alone. Each of those three changes starts learning again. Make one change, wait out the learning, then judge it. Google also notes the algorithm keeps learning after the label goes away.

Bid management used to mean typing numbers next to keywords. Now the machine sets the bid and you manage four things around it.

The target: the CPA or ROAS number you give it. The grouping: Google lets you run a portfolio bid strategy across several campaigns, so you decide which campaigns share one goal. The conversion data: every bid is worked out from what your tracking reports, so a double-counted sale makes the bidding confidently wrong. And the value you send: send revenue and it optimises revenue. Send profit and it optimises profit. Almost nobody sends profit.

Your margin. Google knows what a conversion is worth in revenue, because your tracking tells it. It does not know what the product cost you, what your return rate is, or which SKU makes 60% and which makes 9%. So a Target ROAS of 4 treats a bestseller and a loss-leader as the same product at the same value.

That gap is where the work is, and the fix is old-fashioned. Feed profit into Google in a form it can bid on: tag products by margin, push those tags into Merchant Center custom labels, and set a different target per tier. Then a ROAS goal finally means something.

That is the job Scaley AI does. It reads the account every day and tags every SKU by margin and velocity. Those tags sync into your Merchant Center custom labels daily, so a ROAS target can finally aim at profit. Scaley Suite proposes the change with the reason attached and waits for an individual yes before anything moves. Nothing is automatic. We build Scaley, so weigh that. The track record behind it belongs to ZenoX Media, our sister Google Ads agency, which generated $200M+ in revenue for 300+ ecom brands.

Where we are the wrong pick, honestly. On a small, tidy account with solid conversion tracking, Smart Bidding on Google's defaults is usually enough and it is free. If you want to build your own bidding rules and run them on a schedule, buy a rules workbench instead: Optmyzr's own pricing page lists "Rule Engine-Based Custom Optimizations and Insights" across its Essentials, Premium and Enterprise plans, with "Rule Engine Automations: Hourly* / Daily / Weekly / Monthly / Annually*" at the top tier. Scaley has no rule builder in it. We prepare the moves and wait for you to approve them, which is a different product.