Responsive search ad

An RSA is a pool of text from which Google builds the ad. You supply 3 to 15 headlines of up to 30 characters each and 2 to 4 descriptions of up to 90 characters each, plus at least one final URL. Two optional display path fields, path1 and path2, take up to 15 characters each, and path2 requires path1. Each double-width character in Korean, Japanese or Chinese counts as two.

RSAs carry over into Google’s AI placements. Text ads are one of the formats that can serve in AI Overviews and AI Mode, and Google combines existing campaign assets, including headlines, descriptions, images, pricing and landing pages, to build ads there.

Asset pinning, one of the guardrails that still applies in AI placements, lets you fix a headline or description in place when a message must always appear.

Write each headline so it reads correctly next to any other, since you do not control the combination, and use pinning only for text that must appear, such as a legal line, because pinning narrows the combinations Google can try. Through Admux you supply the copy yourself; Admux never generates ad content. Save headlines and descriptions as copy assets, and Admux screens them against Google’s limits before submission, so a 31-character headline is flagged in Admux instead of being rejected later. The same campaign can carry separate copy for the ChatGPT and Gravity legs, each with its own limits.