KDP categories · Top KDP authors
Calum Marsh: Amazon KDP author data
Calum Marsh has 6 books on Amazon, 6 of them on a best-seller list in the last 30 days (best rank #1), mostly in 21st Century, Social Sciences, Business & Money.
6Books on Amazon
6Listed in 30 days
4.1Average rating
| Median price | $22.87 |
|---|---|
| Price range (middle 50%) | $16.94 – $25.84 |
| Median reviews | 4 |
| Total reviews | 25 |
| New books (30 days) | 6 |
| Breakout books (30 days) | 4 |
What stands out
- 100% of the catalog made a best-seller list in the last 30 days: the whole backlist sells, not one hit.
- Median price $22.87, 123% above the median of their main category, 21st Century.
- 6 new books in the last 30 days, 4 of them broke into a Best Sellers list.
Calum Marsh's best-ranked books
-
The Glass Box: The Shocking True Story of How CrossFit Broke the Rules, Made Millions, and Changed Fitness Forever
by Calum Marsh
- Price$22.79
- Rating3.2
- Reviews8
- Published2026-10
-
The Glass Box: The Shocking True Story of How CrossFit Broke the Rules, Made Millions, and Changed Fitness Forever
by Calum Marsh
- Price$26.80
- Rating3.2
- Reviews8
- Published2026-10
-
The Glass Box: The Shocking True Story of How CrossFit Broke the Rules, Made Millions, and Changed Fitness Forever
by Calum Marsh
- Price$14.99
- Rating3.2
- Reviews8
- Published2026-10
-
True Lies: The Art of Reality Television
by Calum Marsh
- Price$9.99
- Rating5.0
- Reviews1
-
The Glass Box: The Shocking True Story of How CrossFit Broke the Rules, Made Millions, and Changed Fitness Forever
by Calum Marsh
- Price$41.49
- Rating4.5
- Reviews2
-
True Lies: The Art of Reality Television
by Calum Marsh
- Price$22.95
- Rating5.0
- Reviews1
Main categories
About this data
Data comes from KDPTop's daily crawl of Amazon's public Best Sellers pages; medians use the latest list. The opportunity score (0–100, higher is easier to enter) combines the review barrier, the share of low-review books, list turnover, new-release share and price.