Responsive Search Ads: best practices for maximum Ad Strength

Responsive Search Ads (RSAs) are the undisputed standard for search advertising within Google Ads in 2026. Any advertiser aiming for maximum campaign performance needs to build RSAs correctly from the ground up. One of the most decisive factors in that process is Ad Strength: the score Google assigns to the quality and diversity of your ad content. A high Ad Strength does not just improve visibility. It also feeds richer signals to Smart Bidding, leading to lower costs and more conversions. This article explains exactly how to build RSAs that consistently reach "Excellent" status and how to translate that performance into measurable business results.

What are Responsive Search Ads and how does Ad Strength work?

Impact of Ad Strength on CTR

Average CTR improvement per Ad Strength level (2026)

Poor

2%

Average

4%

Good

6%

Excellent

9%

A Responsive Search Ad is an ad format in which you supply up to 15 headlines and 4 descriptions. Google then combines these elements automatically based on the search query, device and user intent. This creates enormous flexibility: in theory, a single RSA can generate up to 43,680 unique ad combinations. That is a fundamental departure from traditional text ads, where every variation had to be created and tested manually.

Ad Strength is the metric Google uses to evaluate how well your RSA is constructed. The score ranges from "Poor" through "Average" and "Good" to "Excellent". Google bases this score on three pillars: the number of unique headlines and descriptions you supply, the degree of diversity (how much the headlines differ from each other in meaning) and the relevance to the keywords in your ad group. A higher Ad Strength increases the probability that your ad will enter relevant auctions and that the algorithm can assemble optimal combinations for every individual searcher.

What many advertisers underestimate is that Ad Strength is not just a quality indicator. It also directly influences how Smart Bidding evaluates your ad. An RSA with "Excellent" status provides richer data for the algorithm, enabling Target CPA and Target ROAS to optimise more precisely. In short, investing in a strong Ad Strength is investing in the overall efficiency of your campaign.

Standard text ads vs. Responsive Search Ads

Standard Text Ad vs. Responsive Search Ad

Key differences in flexibility and performance

Standard Text Ad

• Fixed headlines and descriptions
• No automatic combinations
• Limited testing potential
• Manual A/B tests required
• Lower Ad Strength due to repetition
• Fewer signals for Smart Bidding

Responsive Search Ad (RSA)Recommended

• Up to 15 headlines and 4 descriptions
• Google automatically tests combinations
• High testing potential with no extra effort
• Machine learning continuously optimises
• Higher Ad Strength achievable
• Richer signals for Smart Bidding

The transition from static text ads to RSAs has been a significant shift for many advertisers. Where you previously had full control over which headline paired with which description, RSAs hand part of that control to Google's machine learning system. That might feel uncomfortable, but the performance advantages are substantial.

In practice, well-configured RSAs consistently generate higher CTRs and better Quality Scores than their static predecessors. This is because Google can serve the best-matching combination for each specific search query. A user who types "online driving theory practice test" sees a different ad combination than someone searching for "prepare CBR theory exam", even if both come from the same ad group.

Feature	Standard Text Ad	Responsive Search Ad
Number of headlines	3 (fixed)	Up to 15 (dynamic)
Number of descriptions	2 (fixed)	Up to 4 (dynamic)
Testing capabilities	Manual, per variant	Automatic, continuous
Ad Strength score	Not applicable	Poor to Excellent
Smart Bidding signals	Limited	Rich and diverse
Recommended by Google	No (legacy format)	Yes (standard format)

The 7 most important best practices for maximum Ad Strength

Reaching "Excellent" status requires a deliberate approach. Below are the seven most impactful best practices that AdBrains applies across all client campaigns, including concrete steps for implementation.

1. Write at least 8 to 10 unique headlines

Google recommends a minimum of 8 to 10 headlines to create sufficient variation. The more unique headlines you supply, the more combinations the algorithm can test and the faster you reach "Excellent" status. Aim for the maximum of 15 headlines when you have enough distinct messages to share.

2. Ensure genuine content diversity

Google evaluates not only the quantity of headlines but also how meaningfully they differ from each other. Write headlines that each highlight a different aspect of your offer: price, uniqueness, benefit, urgency, guarantee and ease of use are all strong angles. Avoid headlines that say essentially the same thing with different words.

3. Include your primary keyword in at least two headlines

Relevance is a core component of Ad Strength. Make sure your main keyword, or a close variant, appears in at least two of your headlines. This improves both Ad Strength and Quality Score, because Google can see that the ad aligns with the search query.

4. Use pinning sparingly and strategically

The pin feature lets you lock a specific headline to position 1, 2 or 3. This gives control but also limits the number of combinations Google can test. Use pinning only when there are legal or compliance reasons to always display a specific message. In all other cases, let the algorithm do its work.

5. Write two fully unique descriptions per slot

With four description slots available, there is ample room to convey diverse messages. Write a unique description for each slot, each with its own focus or call-to-action. Make use of the full character limit (90 characters per description) to deliver maximum value.

6. Include at least one action-oriented description

Ensure that at least one description contains a clear call to action, such as "Start your free trial today" or "Sign up for the practice test now." Action-oriented descriptions improve CTR and send a strong signal to Google about the intent of the ad.

7. Review combination insights regularly

In the Google Ads dashboard, each RSA has a "Combination insights" tab. This shows which headline and description combinations Google has displayed most frequently and which have performed best. Use this data to replace underperforming headlines with stronger alternatives, steadily growing Ad Strength over time.

Case study: ToetsJeKennis.nl

RSA Performance at ToetsJeKennis.nl

Results after full RSA optimisation in Google Ads

+34%

More conversions

Excellent

Ad Strength achieved

+28%

Higher CTR

-19%

Lower CPA

To illustrate how these best practices work in the real world, ToetsJeKennis.nl serves as a concrete example. ToetsJeKennis.nl offers online practice tests for the Dutch CBR driving theory exam and partners with AdBrains to consistently reach new learners through Google Ads.

At the start of the collaboration, the RSAs for ToetsJeKennis.nl averaged an Ad Strength of "Average". The headlines were not sufficiently diverse in content, and only seven headlines were used per ad. Additionally, nearly all headlines were pinned to fixed positions, which severely limited the algorithm's room to test combinations.

After a thorough revision based on the best practices described above, the RSAs were completely rewritten. For each ad group, 13 to 15 unique headlines were crafted from different angles: the advantages of the practice test, user pass rates, platform ease of use and urgency around the CBR exam. Pins were removed except for the single most important USP that always needed to remain visible. Descriptions were expanded to all four slots, each with a distinct focus.

The result: within eight weeks, the vast majority of RSAs reached "Excellent" status. Campaigns showed a 28% increase in CTR, conversions rose by 34% and CPA dropped by 19%. That CPA reduction is a direct result of the richer signals Smart Bidding received through the improved Ad Strength, enabling Target CPA to optimise with greater precision.

Ad Strength and its relationship with Smart Bidding and Quality Score

Ad Strength does not exist in isolation. It is closely connected to two other fundamental Google Ads concepts: Smart Bidding and Quality Score. Understanding how these three elements work together is essential for any serious advertiser.

Quality Score is built from three components: expected CTR, ad relevance and landing page experience. An RSA with high Ad Strength typically scores better on the first two components, because Google can assemble more relevant combinations for every search query. A higher Quality Score in turn leads to a lower CPC at the same ad position, directly improving budget efficiency.

Smart Bidding strategies such as Target CPA and Target ROAS use hundreds of signals to adjust bids in real time. The quality and diversity of your RSA content is one of those signals. An "Excellent" Ad Strength expands the bidding room available to the algorithm: it can bid more frequently and with greater confidence in relevant auctions, leading to more impressions with the right audience and ultimately more conversions at lower cost.

Checklist: is your RSA ready for maximum Ad Strength?

Use the checklist below to quickly assess whether your current RSAs meet the requirements for "Excellent" Ad Strength.

• You have written at least 10 unique headlines per ad.
• Each headline highlights a different benefit, USP or keyword.
• Your primary keyword appears in at least two headlines.
• You are using all four description slots.
• Each description contains a unique message or call-to-action.
• You are using the full character limit (30 characters per headline, 90 per description).
• Pins have been minimised or removed entirely.
• You review Combination insights monthly and replace weak headlines.
• Your Ad Strength score shows "Good" or "Excellent" in the dashboard.
• Your RSA is aligned with the search intent of the ad group.

Common RSA mistakes and how to avoid them

Even experienced advertisers regularly make mistakes when setting up RSAs that unnecessarily suppress Ad Strength. Below are the most common pitfalls and how to avoid them.

• Writing too few headlines: Many advertisers stop at five or six headlines. This limits diversity and keeps Ad Strength low. Always write at least 10, ideally 15 headlines.
• Headlines that are too similar: Google recognises semantic similarity. If three headlines are all variations of "Take the practice test now", that barely counts as diversity.
• Overusing pins: Pins provide control but cost flexibility. Use them only when genuinely necessary.
• No action-oriented language: RSAs without a clear call-to-action miss opportunities to boost CTR. Every ad should direct the visitor somewhere with purpose.
• Never revisiting RSAs: Online competition and keyword trends change constantly. Advertisers who set RSAs once and forget them miss growth opportunities. Schedule quarterly reviews.
• Repeating the same message in headlines and descriptions: Headlines and descriptions should complement each other, not repeat the same point. Use the headline to capture attention and the description to persuade.

Frequently asked questions about Responsive Search Ads and Ad Strength

What minimum Ad Strength should I aim for to achieve good campaign performance?

Google advises aiming for at least "Good", but in practice the largest performance gains only appear at "Excellent". Ads with "Excellent" status typically generate significantly more impressions and higher CTRs than ads at "Good" or below. Always aim to bring every RSA to "Excellent", even if that takes a little more time in the copywriting phase. The investment pays back quickly through lower CPCs and higher conversions.

How many RSAs should I use per ad group?

Google recommends at least one RSA per ad group, but for optimal testing opportunities AdBrains recommends working with two to three RSAs per group. This allows you to test meaningfully different angles, such as one RSA focused on price, one on quality and one on urgency. Make sure you have sufficient search volume to collect statistically significant data across multiple ad variants. In smaller ad groups, one strong RSA with maximum Ad Strength is more effective than three average variants.

Does Ad Strength affect my Quality Score?

Ad Strength and Quality Score are two separate metrics, but they influence each other indirectly. Ad Strength measures the diversity and quality of your RSA content, while Quality Score looks at expected CTR, ad relevance and landing page experience. A high Ad Strength increases the probability of higher ad relevance and expected CTR, which contributes to a better Quality Score. In this way they operate as a positive feedback loop: better Ad Strength leads to a better Quality Score, which leads to lower CPCs and more conversions.

When should I replace or rewrite an RSA?

An RSA should be revised if its Ad Strength remains at "Average" or lower for an extended period, if its CTR falls significantly below the ad group average, or if the Combination insights show that only a handful of headlines are receiving nearly all impressions. The latter signals that the remaining headlines are not relevant enough for the target audience. Schedule a quarterly review for all RSAs at minimum, so you stay aligned with current search trends and competitive positioning.