What is an ad group in Google Ads, and how is a campaign different?

Google Ads is organized into three layers: account, campaigns and ad groups. Keywords and ads sit inside the ad groups. This is what each level holds, in Google’s words, and the most of it Google allows:

The limits are from Google’s page on account limits. The 10,000 campaigns count active and paused ones. Local and App campaigns stop at 100 ad groups. Targeting items are keywords, placements and audience lists, and the 3 is enabled responsive search ads in one ad group. None of these is advice: the same page says that generating a large number of ad groups or campaigns with few creatives or keywords in each may undermine the stability of Google’s systems, and that Google may throttle or exclude them.

The Google Ads hierarchy runs downward. Google says a status change at the campaign level affects the ad groups, ads and keywords within it: pause a campaign and all of them are paused with it. Pause one ad group and its ads and keywords pause, while the campaign’s other ad groups stay enabled.

A campaign, in Google’s glossary, is a set of ad groups that share a budget, location targeting and other settings. So the difference between a campaign and an ad group is what is shared. A campaign’s settings are one answer for every ad group in it, and an ad group’s are its own:

Three rows need a note:

• Languages. Google says that, starting in September 2026, the campaign-level language setting will be removed from Search campaigns, whose ads will match on the language they’re written in.
• Bids. Under manual bidding the ad group’s default bid covers its keywords, and a keyword’s own bid overrides it: in Google’s example, a keyword raised to $0.60 uses that in an ad group whose default is $0.50. With automated bidding, Google says, it sets the default bids for you.
• Targets. Under Target CPA or Target ROAS an ad group can take a target of its own. Google says this isn’t recommended, as it can restrict Smart Bidding.

Which one to create follows from the table. Google’s rule is to create a separate campaign when you need a different set of campaign settings, such as a budget or location targeting: a clothing store that wants one budget for shirts and another for pants needs a campaign for each. If all your ads share a budget and target the same locations, one campaign will do. Google’s page on account structure draws the whole rule as a diagram: keywords that share a budget or target belong in the same campaign, and keywords that share the same landing page and creative themes belong in the same ad group.

Google asks for a narrow theme. Its page on organizing an account says to pick one for each ad group and use keywords related to that theme. For many businesses, it says, the way your website is structured is a good place to start, with each ad group representing a different page or category of the site.

For Search campaigns on Smart Bidding, Google’s page on account structure adds this: “Simpler structures with consolidated, tightly-themed setups unlock better performance, easier campaign management, clearer trends, and fewer errors.” Its first step is to move single-keyword ad groups into themed ad groups, because grouping keywords into similar themes makes it easier for Google to understand the keywords, select the best one, and determine which ad should serve for each query. It also says that segmented traffic forces Smart Bidding to optimize for multiple targets separately, potentially reducing efficiency.

The keywords per ad group guide covers how many keywords and ads an ad group wants, and what became of single-keyword ad groups.

The Campaigns table gives a campaign one row, and a good row can hide an ad group that isn’t earning its share. The ad groups of one campaign share its budget, its locations and its bidding, so they can be set against each other.

1. 01Go to Campaigns › Ad groups and select the campaign. Google Ads then shows the campaign’s performance broken out by its ad groups.
2. 02Set the date range to the last 13 whole weeks. The table opens on the last 30 days, which is rarely long enough for a small ad group’s conversions to add up.
3. 03Select the columns icon above the table, then Modify columns, and add Conversions and Cost / conv. Where your conversions carry values, add Conv. value / cost too, which is conversion value divided by cost.
4. 04For each ad group, subtract its row from the totals at the bottom of the table. What is left is the campaign’s other ad groups: divide their cost by their conversions for what they paid for one.
5. 05Divide the ad group’s cost by that price. The answer is what its spend would have bought at the others’ price. An ad group that brought under half of it is the one to open.
6. 06Check that it isn’t one bad stretch. Select the segment icon, then Time, then Week, which splits each row into its weeks. Google segments by Day only for date ranges of 16 days or less.

A small ad group can bring nothing by luck, so test the gap before you act on it. In Google Sheets, =BINOMDIST(4, 65, 0.327, TRUE) gives the chance that an ad group taking 33% of a campaign’s spend would bring 4 or fewer of its 65 conversions: about 1 in 3.5 million. Multiply it by the number of ad groups you compared, since each one was another chance for luck to show. Cedar & Pine compared 11, and 1 in 320,000 is still far under 5%.

What you can do about it depends on how the campaign bids:

• Manual bidding. Lower the ad group’s default bid: tick it on the Ad groups table, select Edit, then Change bids, enter a new default max. CPC and select Apply. A keyword with a bid of its own keeps that bid.
• Target CPA or Target ROAS. The ad group can take a target of its own, with Google’s caution above. The Target CPA and Target ROAS guide covers targets.
• Automated bidding with no target. The ad group has no bid of its own to change. Read the searches it buys first, and add the ones that never convert as negative keywords, which the negative keywords guide covers. To hold it to a figure of its own, move it to a campaign with a budget and a target of its own: tick the ad group, select Edit, then Copy, open Edit again and select Paste, pick that campaign in the campaign picker, and select Done, then Paste. Then pause the original from the same Edit menu. Move the one ad group and leave the rest: Google warns that reorganizing an account after it has run “wipes out all the valuable data you’ve accumulated, possibly affecting how your ads perform.”

Keywords in two ad groups can match one search. Google says they don’t compete with each other in the auction: only one of them can trigger an ad for that search. It picks in this order:

• An exact match keyword identical to the search. Google counts a spell-corrected search as identical, and a plural or a synonym as not.
• A phrase or broad match keyword identical to the search.
• Relevance. Where no keyword is identical, Google says only the most relevant ad groups are matched, judged by the meaning of the search, all the keywords in an ad group, and the landing pages within it.
• Ad Rank. Among keywords of equal priority, the one whose ad has the highest Ad Rank.

Google’s advice follows from the third: “Structure your ad groups thematically to clarify which ad group should match for a given search.” Where two ad groups are about as relevant, Google says the keyword with the higher Ad Rank enters the auction, so either can answer the search, each with its own ad and page. To see where that happens:

1. 01Go to Campaigns › Insights and reports › Search terms and set the date range to the last 30 days.
2. 02Select the columns icon, then Attributes, and tick Keyword. The column isn’t shown by default, and it says which of your keywords matched each search.
3. 03Download the report and sort it by search term. A search that sits beside keywords from two ad groups of one campaign was paid for by both.
4. 04Decide which ad group’s ad and page answer that search, and add the search there as an exact match keyword. An identical exact match keyword comes first in Google’s order, so that ad group takes the search whenever its keyword is eligible to serve.

A search can still go elsewhere when the ad group you meant wasn’t eligible. Google’s reasons include a keyword marked low search volume, an ad group whose ads or landing pages are all disapproved, and a campaign whose budget is too low to take all its traffic. Google also says that for searches made through Lens, AI Mode, AI Overviews or autocomplete, the search term in your report is its best approximation of what the person meant, and a keyword may not be prioritized. Where the same keyword sits in both ad groups, the duplicate keywords guide covers which copy to keep.

Google recommends a campaign name that clearly describes the campaign’s theme, so you can find it in your account, and says the name isn’t visible to your customers. Where its ads show is another setting, Locations: a campaign’s ads are eligible to show to customers in the locations it targets.

The two drift apart when a campaign is copied. Google says a pasted campaign has the same structure and settings as the original, targeting settings among them, so a copy renamed for another market still targets the first one until somebody changes it.

1. 01Go to Campaigns › Campaigns and select the Settings tab.
2. 02Read each campaign’s locations against the market its name says.
3. 03To change several at once, tick them, open the Edit menu and select Change locations. You can replace their locations or add to them.

The location targeting guide covers who a location setting reaches once it is right.

Every day Goldbeater adds up the last 13 whole weeks of every ad group in your Search, Shopping and Display campaigns, and sets each enabled ad group against its campaign’s other ad groups a week at a time, so a week the whole campaign did badly counts against all of them alike. It raises an ad group that spent $20 or more where all of these hold:

• Under half. It brought under half the conversions its spend would have bought at the other ad groups’ rate. Where your conversions carry real values, its return is under half theirs too.
• Not luck. So few would be unlikely by chance after allowing for every ad group tested in the account, at 5% overall.
• No target, and not bidding for impressions. The campaign has no target CPA or target ROAS of its own, and doesn’t bid for impressions, as Target impression share does. Where it has a target, Goldbeater drafts one for the ad group instead, and the Target CPA and Target ROAS guide covers that finding.
• Not still a good buy. An ad group far below its own campaign that still returns more than your other campaigns typically do isn’t raised.

A keyword Goldbeater raises on its own for converting far below its campaign is taken out of its ad group’s figures first, so one fact isn’t reported twice.

That is the table’s first row. The finding’s 29.7 expected conversions are the sum worked above, done a week at a time, and its chart sets the five ad groups against the campaign’s return. What to do follows how the campaign bids. Under Manual CPC the finding names the ad group’s default bid to lower. Under automated bidding with no target, as here, there is no bid of the ad group’s own, so it says to read the searches it buys, then to give it a campaign with a target of its own or pause it. An ad group that converted nothing is one to pause, once you’ve read what it buys. Goldbeater drafts no change for this finding.

Sofas — general turns up in two more guides. The keywords per ad group guide counts its keywords, and the landing page guide reads the page it sends clicks to.

Goldbeater also raises a search that two or more ad groups of one Search campaign paid for in the last 30 days, where the search converted in that campaign, no exact match keyword in the campaign is that search, and no negative keyword blocks it. The ad group whose keyword is the longest part of the search keeps it, or else the one that converted it most, and the finding’s figure is what the other ad groups spent on it: raised from $20, and high from $200. Goldbeater drafts the search as an exact match keyword in the ad group that keeps it. The change is recommended where a keyword there is part of the search, and offered where none is.

And it reads your campaign names. It raises an enabled campaign whose name says a country, a region or a market, such as UK, EMEA or Germany, and that targets a location outside every place the name says, or no location at all. You keep no list of codes: a piece of a name counts where most of your campaigns that carry it target what it stands for, by more than chance would give, or where it is a country’s own name that none of your keywords or product titles holds. On Display, Video, Demand Gen, App and Performance Max campaigns it reads a language in the name against the campaign’s languages the same way, and it leaves a Search campaign’s language alone, since Google is removing that setting. Which is wrong, the name or the targeting, is yours to say, so the finding is advice.

The audit checklist has each of these lines with where to find it in Google Ads.

What is an ad group in Google Ads?

In Google’s definition, an ad group contains one or more ads that share similar targets. In a Search campaign those targets are keywords, so an ad group is a list of keywords and the ads written for them. Each campaign is made up of one or more ad groups.

What is the difference between a campaign and an ad group?

A campaign is a set of ad groups that share a budget, location targeting and other settings, such as bidding, networks and the ad schedule. An ad group sits inside one campaign and holds the keywords and ads for one theme. What every ad group shares is set on the campaign. What differs by theme is set on the ad group.

When should I create a new campaign instead of a new ad group?

Create a campaign when you need a different set of campaign settings, such as a budget or location targeting. Create an ad group when the settings can be shared and the keywords need their own ad or landing page. Google’s diagram says keywords that share a budget or target go in the same campaign, and keywords that share landing page and creative themes go in the same ad group.

Can an ad group have its own budget?

No. On Google’s pages the average daily budget is set for each campaign, and every ad group in the campaign draws on it. To give a set of keywords a budget of its own, put it in a campaign of its own.

Can an ad group have its own bid?

Under manual bidding, yes: each ad group has a default bid, and a keyword’s own bid overrides it. With automated bidding Google sets the bids. Under Target CPA or Target ROAS an ad group can take a target of its own, which Google says isn’t recommended because it can restrict Smart Bidding.

What are Google’s limits on campaigns and ad groups?

An account can hold 10,000 campaigns, active and paused, and a campaign 20,000 ad groups, or 100 in a Local or App campaign. An ad group can hold 20,000 targeting items and 3 enabled responsive search ads. They are limits, not advice.

Does Performance Max have ad groups?

A Performance Max campaign is built from asset groups. Google defines an asset group as a collection of creatives centered on a theme or related to a target audience, and recommends basing them on the sections or categories of the products on your website, much as it suggests for ad groups.