The essentials
- Definition: the RSA (Responsive Search Ad) is Google Ads' standard text ad format on search: up to 15 headlines and 4 descriptions that the algorithm combines according to the query and the user.
- Since 2022: the only search ad format you can create; expanded text ads can no longer be made.
- 2026 benchmarks: a CTR of 4 to 8% on the Search Network, over 20% on brand queries; 10 to 15 distinct headlines and 3 to 4 descriptions for an "excellent" ad strength.
- The rules: varied headlines (keyword, benefit, proof, call to action), limited pinning, complete extensions, tests by ad group.
Enhanced measurement RSA (Responsive Search Ad) is Google Ads' text ad format on search results. The advertiser supplies up to 15 headlines and 4 descriptions; at each impression, the algorithm selects and assembles up to 3 headlines and 2 descriptions according to the query, the device, the user's history and past performance. Since June 2022 it has been the only search ad format you can create. Building a complete campaign is covered in creating an effective Google Ads campaign.
How the algorithm assembles an RSA
| Element | Number supplied | Number shown | Maximum length |
|---|---|---|---|
| Headlines | 3 to 15 | 2 or 3 | 30 characters |
| Descriptions | 2 to 4 | 1 or 2 | 90 characters |
| Display URL (paths) | 2 fields | As space allows | 15 characters each |
| Extensions (sitelinks, callouts, structured snippets, calls, prices) | Unlimited by type | By position and space | Variable |
Google learns which combinations get the best click-through and conversion rate in each context, and favours them. The advertiser can pin a headline to a position (headline 1 always carries the brand, for instance), at the cost of reducing the possible combinations. The "ad strength" indicator (poor, average, good, excellent) measures the variety and relevance of what you supplied, with no direct link to performance.
Writing an effective RSA
- Varied headlines: 10 to 15 headlines covering the ad group's keyword, the main benefit, a proof point (reviews, a figure, years in business), an offer, a call to action, the location, the brand. Headlines repeating the same idea reduce the useful combinations.
- The keyword in several headlines: at least three headlines contain the keyword or a close variant, for relevance and for the Quality Score.
- Complete descriptions: 3 to 4 descriptions of 80 to 90 characters, each readable on its own, with a benefit, a proof point and an action.
- Minimal pinning: pin at most one headline (position 1) when a mention is mandatory; pinning three headlines turns the RSA into a fixed ad.
- The extensions: sitelinks, callouts, structured snippets, calls, prices; they raise CTR by 10 to 20% and the space taken up; see Google Ads ad extensions.
- Two RSAs per ad group: one benefit-led, one proof- or offer-led, so you can compare; see A/B testing in Google Ads.
Reading an RSA's performance
- CTR: 4 to 8% on average on the Search Network in 2026, over 20% on brand queries; it compares against the Quality Score's expected CTR. The definition is in CTR: definition.
- Conversion rate and cost per conversion: the only metrics you decide on; an RSA with a high CTR can convert less than a plainer one.
- The asset report: for each headline and description, the number of impressions and a performance rating (low, good, best); "low" assets get replaced after a few thousand impressions.
- The combinations report: the assemblies shown most often; useful for checking the combinations make sense.
- Ad strength: aim for "good" or "excellent", without making it an end in itself.
The frequent mistakes
| Mistake | Effect | Fix |
|---|---|---|
| Only three headlines | Few combinations, limited learning | 10 to 15 distinct headlines |
| Redundant headlines ("Free quote", "Quote at no cost", "No-charge quote") | Repetitive combinations, poor ad strength | One headline per idea |
| Full pinning | A fixed ad, no optimisation | At most one pinned headline |
| No keyword in the headlines | Falling relevance and Quality Score | The keyword in 3 headlines or more |
| No extensions | A less visible ad, a lower CTR | Every relevant extension |
| An ad group that is too broad | Generic headlines, poor relevance | One group per intent; see keyword match types |
How GreenRed helps
Rather than juggling several tools, GreenRed's SEA tracking and optimisation brings these metrics together in a single dashboard, compares them over time and tells you which actions come first. You can try it free, with no card, from the Pricing.
Frequently asked questions
What is a responsive search ad (RSA)?
Google Ads' text ad format on the Search Network: the advertiser supplies up to 15 headlines and 4 descriptions, and the algorithm assembles the combination best suited to the query and the user at each impression. It has been the only creatable search format since 2022.
How many headlines and descriptions should you supply?
Ten to fifteen distinct headlines (keyword, benefit, proof, offer, call to action, location, brand) and three to four complete descriptions. Variety counts for more than number: headlines repeating the same idea reduce the useful combinations.
Should you pin headlines?
At most one headline, in position 1, when a mention is mandatory (brand, compliance). Pinning three headlines turns the RSA into a fixed ad and removes the optimisation. If control is essential, create two RSAs, one pinned and one free, and compare.
How do you know whether an RSA is working?
By conversion rate and cost per conversion, compared with the second RSA in the same ad group. CTR (4 to 8% on average) and ad strength are diagnostic indicators; the asset report tells you which headlines to replace.