Diary Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

Taja is the best-performing diary brand in July 2026, moving 19,000 units across 3 ASINs for 39.6% of Top 10 volume. Blissful Diary follows with 8,000 units (16.7%), ahead of Amazon Basics on 7,000 units (14.6%).

With 7 brands splitting the Top 10 and 70.8% of volume sitting with three of them, this is a concentrated shelf — the leaders hold multiple listings or one very high-velocity ASIN, so a new entrant competes against established review moats rather than an open field. Average selling prices among the leaders run from $5.82 to $47.99, 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: B0CX1RDX77 booked 3K units at $5.93, with ▲ 50.0% MoM change. On the growth side, B0G6YS8K85 leads positive momentum with ▲ 133.3% MoM growth on 700 units, with B0BXX1TJC8 close behind at ▲ 100.0% MoM on 2K 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already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date.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.