Grout Pen Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

Zep is the best-performing grout pen brand in July 2026, moving 10,000 units across 1 ASIN for 18.9% of Top 10 volume. Goopreen follows with 10,000 units (18.9%), ahead of Slobproof on 8,000 units (15.1%).

Volume is spread across 10 brands, with the top three holding 52.8% between them. No single label controls the shelf, which usually leaves room for a well-differentiated listing to take share without outspending an incumbent. Average selling prices among the leaders run from $9.80 to $12.99, which frames the price band a competing listing has to justify.

Based on July 2026 data, this shortlist surfaces the two kinds of ASIN worth keeping an eye on — the ones that just broke into the Top 10, and the ones growing fastest month over month. Specifically, one ASIN forced its way in: B07M7L92LW booked 2K units at $25.99, with ▲ 0.0% MoM change. On the growth side, B08SC6X17G leads positive momentum with ▲ 100.0% MoM growth on 400 units, with B08SCFF8RM close behind at ▲ 100.0% MoM on 400 units.

The two signals carry different weight. A fresh entrant means share has already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date. A steep growth rate works as the earlier warning: it marks demand that is still compounding, usually a month or two before the ranking catches up to it.