How Google Responsive Search Ads work
A Responsive Search Ad (RSA) is the standard text ad on Google Search. Instead of writing one fixed ad, you give Google up to 15 headlines (30 characters each) and up to 4 descriptions (90 characters each). Google then mixes and matches them, showing up to 3 headlines and 2 descriptions at a time, and learns which combinations get the most clicks for each search.
Google’s ad strength meter rewards variety: give it headlines that say different things (the keyword, benefits, the offer, trust signals, a call to action) rather than 15 versions of the same sentence. Our generator builds exactly that mix.
Writing ads that convert
- Mirror the search. Put the main keyword in at least 2–3 headlines. Relevance lifts both CTR and Quality Score.
- Lead with benefits, not features. “Save 10 hours a week” beats “Automated reconciliation”.
- Make one clear offer: a free trial, a discount, free delivery or a free quote.
- Add proof: ratings, customer numbers, years in business, awards.
- Use a specific call to action. “Book a free demo” tells people exactly what happens next.
- Pin sparingly. Pinning a headline to position 1 guarantees it shows, but reduces Google’s ability to optimise.
Facebook & Instagram ad text limits
| Field | Recommended | What happens if longer |
|---|---|---|
| Primary text | ≤ 125 characters | Cut off with “See more” in most placements |
| Headline | ≤ 40 characters | Truncated on mobile feed |
| Description | ≤ 30 characters | Often hidden entirely on mobile |
Always test. Launch 3–5 primary texts and headlines with Meta’s multiple text options (or Google’s RSA assets). After a week or two, pause the weakest and write new variations inspired by the winners. Small copy changes often move conversion rates by 20–50%.