Last checked against Google’s documentation on 5 October 2026.
What are responsive search ads?
Responsive search ads (RSAs) are the standard text ad in Google Ads Search campaigns. Instead of writing one fixed ad, you give Google a set of headlines and descriptions, and Google assembles them into different combinations for each search, learning over time which ones perform best. Google’s responsive search ads page is the source for the limits and pinning rules in this guide.
That flexibility changes the job. You are no longer writing an ad; you are writing a set of parts that must read well in any order, and you judge the ad as a whole rather than each version. This guide covers the limits, how to write the parts, when pinning is worth it, what Ad Strength does and doesn’t do, how to read the asset and combinations reports, how many RSAs an ad group needs, and how to test them without guessing.
RSA limits: headlines, descriptions, and characters
Not every part shows every time. Google says text in Headline position 1 and Description position 1 usually appears, while the second and third headlines and the second description may appear based on what is predicted to perform best, or when there’s enough space. So make sure every headline and description that could land in those first positions works on its own.
The final URL is shared by every combination. If headlines speak to different products or offers, the landing page has to serve all of them, which is why a tight ad group matters more with RSAs, not less. More on that in our Google Ads landing page guide.
How to write headlines and descriptions that work together
Google’s best practices for responsive search ads say to add as many unique headlines and descriptions as you can, include your keywords in the text, and try headlines of varying lengths. In practice, a full set of 15 headlines is easiest to write by role:
| Role | How many | What it says |
|---|---|---|
| Keyword / what it is | 3–4 | The product, service, or category in the searcher’s words, with variations |
| Benefit | 3–4 | The outcome for the customer, not the feature list |
| Proof | 2–3 | Reviews, years in business, number of customers, certifications you can back up |
| Offer or price | 2 | A price from, a free trial, free shipping, a quote within a set time, if true |
| Next step | 2 | Book a call, get a quote, start a trial, shop now |
Each headline must make sense next to any other. Avoid two headlines that repeat the same words, because Google may show them together; avoid a headline that only makes sense after another (“And it’s free”). Use the four descriptions for longer reasons to choose you, each complete on its own.
Fit the copy to the business. An online shop might lead with product range, delivery, and returns. A lead generation business might lead with the service area, response time, and a free quote. A SaaS product might lead with the job the software does, integrations, and the trial. The structure is the same; the facts come from your own business.
Pinning: when it is worth the trade-off
Pinning fixes a headline or description to a position. Google says pinning reduces the number of headlines or descriptions that can be matched to a search, isn’t recommended for most advertisers, and can affect Ad Strength. It also says text that must appear in every ad has to be pinned to Headline position 1, Headline position 2, or Description position 1, because content pinned to Headline position 3 or Description position 2 isn’t guaranteed to show.
Pin when:
- A legal or regulatory disclaimer must appear in every ad.
- Your brand name must lead, for example in a brand campaign where a competitor’s name could otherwise be confused with yours.
- A headline only makes sense in one position, and you can’t rewrite it to stand alone.
When you pin, pin two or three alternatives to the same position. Google’s own example: pin a second headline to Headline position 1 and every ad shows one of the two there. That keeps the control you need while leaving the system something to test. Pinning a single headline to each of the three positions leaves nothing in the headlines to test.
Ad Strength: what it is and what it isn’t
Ad Strength rates a responsive search ad as Incomplete, Poor, Average, Good, or Excellent. Google’s Ad Strength page describes it as a tool that helps you provide a sufficient and relevant mix of assets, recalculated whenever you change keywords, assets, or account structure. To see it for every ad, open Ads, select the columns icon, open Attributes, and add Ad strength.
The feedback it gives is still useful: add more headlines, make them more unique, include popular keywords, and pin less. Google also lists sitelinks among the inputs, suggesting at least six across ad group, campaign, and account level for a Good rating or better. Where Ad Strength and results disagree, results win: if a “Good” ad has twice the conversion rate of an “Excellent” one in the same ad group, keep the “Good” one. Ad Strength is separate from keyword Quality Score, which rates expected CTR, ad relevance, and landing page experience.
Google Ads assets around the ad
Headlines and descriptions are only part of what shows. Google’s assets page lists the other assets a Search ad can carry, including sitelinks, callouts, structured snippets, images, calls, locations, prices, promotions, and lead forms. Google notes that an approved asset still isn’t guaranteed to show, and that ads with more assets often have a higher actual CPC because they are more prominent.
- Sitelinks should point to distinct, useful pages: pricing, a category, a case study, contact. Not four copies of the home page.
- Callouts carry short facts that don’t fit in a headline: delivery terms, support hours, a guarantee.
- Structured snippets list a set of things under a fixed header, such as types, services, or brands.
Don’t repeat the same line as a headline and a callout. Each slot is space you can use to say something new.
Asset reporting and the combinations report
The ad-level asset report
In Campaigns, open Ads, find the responsive search ad, and select View asset details under it. Google’s ad-level asset report page says the old Performance label column (Low, Good, Best) has been deprecated, and full statistics per asset (impressions, clicks, conversions, conversion value, and cost) are now available for dates from 5 June 2025. For every RSA across a campaign or the account, use Assets in the Campaigns menu, described on the campaign-level asset reporting page.
Read those numbers with Google’s caveats in mind. Several assets show in one impression, so asset metrics don’t add up to the ad’s totals, and Google says ratio metrics at asset level, such as CTR, CPA, or ROAS, are directional only. The most useful signal is often impressions: Google serves the assets it predicts will work, so a headline that gets a tiny share of impressions after a few weeks is one the system has stopped choosing.
- Shown regularly
- Rarely chosen
View as table
| Item | Impressions | Group |
|---|---|---|
| Keyword headline A | 4,200 | Shown regularly |
| Benefit headline | 3,100 | Shown regularly |
| Keyword headline B | 2,600 | Shown regularly |
| Offer headline | 1,900 | Shown regularly |
| Proof headline | 380 | Rarely chosen |
| Generic slogan | 120 | Rarely chosen |
The combinations report
From the same View asset details page, the Combinations tab shows which headline and description combinations were shown, ranked by impressions. Google’s combinations report page warns it shouldn’t be used to create static versions of your RSAs, because the same combinations aren’t guaranteed to perform the same. Use it to check how the ad actually reads to people: whether two headlines that repeat each other appear together, or a combination says something you didn’t intend.
How many RSAs per ad group?
Google’s best practices recommend at least two responsive search ads with Good or Excellent Ad Strength per ad group. Two gives you a comparison inside every ad group. More than two splits a limited number of impressions further, so in a low-volume ad group each ad takes longer to show a clear result. A sensible default is two or three RSAs in your highest-spend ad groups, and one strong RSA plus a challenger where volume is low.
Check the ad rotation setting while you are there. Google’s ad rotation page describes two options: Optimize: Prefer best performing ads, which favours ads expected to perform better, and Do not optimize, which rotates ads more evenly and isn’t recommended for most advertisers. Leave it on Optimize unless you are running a deliberate manual test.
How to test responsive search ads
Testing RSAs is less about one ad beating another and more about feeding the system better parts. Two approaches work:
- Replace weak assets in place. Swap the headlines the system rarely chooses for genuinely new angles. Note that in the Google Ads interface, saving edits to an ad creates a new version that goes for review (see Google’s editing ads page), so log the date and compare before and after.
- Run an ad variation. Under Campaigns, Experiments, Ad variations, you can test a change across many RSAs at once: find and replace text, update headlines and descriptions (including pinning), or update URLs, with an experiment split you choose. Google’s ad variations page has the steps. This is the cleanest way to test a message, such as a new offer or call to action, across a whole campaign.
- ReadAsset impressions and the ad’s conversions and cost per conversion against the other ads in the ad group.
- ReplaceTwo or three rarely chosen headlines with new angles, not rewordings.
- WaitUntil the ad has enough clicks and conversions to compare equal periods.
- JudgeOn conversions and cost per conversion, not CTR or Ad Strength alone.
Judge the ad by the result you bid for. A headline that lifts CTR but lowers conversion rate is attracting the wrong clicks; our Google Ads CTR guide covers when a high CTR is a bad sign. Change one thing per ad group at a time so you can tell what moved the numbers.
An RSA review in seven steps
- Add Ad strength, conversions, and cost per conversion to the Ads view and sort by cost.
- Find ad groups with only one enabled RSA and add a second.
- Find RSAs with fewer than 15 headlines or 4 descriptions and fill the gaps with distinct roles.
- Remove pins that aren’t required; where a pin is required, pin two or three alternatives.
- Open View asset details and replace headlines with a tiny share of impressions.
- Read the Combinations tab for repeated or awkward pairings.
- Check sitelinks, callouts, and structured snippets, then compare equal periods after a few weeks.
In Boxoo, the creative and landing pages agent reviews your responsive search ads every day and flags those with low Ad Strength or results well below the other ads in their ad group. It can prepare a new responsive search ad, pause or re-enable an ad, and add or remove sitelinks, callouts, and structured snippets. Google Ads doesn’t allow editing an existing ad’s text through the API, so for copy changes Boxoo offers a replacement ad instead. Nothing changes until you press Apply.
Run a free Google Ads audit to see which of your responsive search ads are costing you conversions.
