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Ryan Castledine: Amazon KDP author data
As of Nov 6, 2026, Ryan Castledine has 6 books on Amazon, 4 of them on a best-seller list in the last 30 days (best rank #9), mostly in Ancient Civilizations, Civilization & Culture, World.
| Median price | $22.99 |
|---|---|
| Price range (middle 50%) | $13.24 – $31.99 |
| Median reviews | 1 |
| Total reviews | 168 |
| New listings (30 days, incl. new editions) | 4 |
| Breakout books (30 days) | 3 |
What stands out
- 67% of the catalog made a best-seller list in the last 30 days: the whole backlist sells, not one hit.
- Median price $22.99, 52% above the median of their main category, Ancient Civilizations.
- 4 new listings in the last 30 days (new editions included), 3 of them broke into a Best Sellers list.
Ryan Castledine's best-ranked books
-
Ruined Earth: A Definitive Guide to the Lost World
by Ryan Castledine
- Price$22.99
- Rating5.0
- Reviews1
-
Life Before The Flood: A Definitive Guide to the Lost World
by Ryan Castledine
- Price$38.99
- Rating4.1
- Reviews83
- Published2026-09
-
Ruined Earth: A Definitive Guide to the Lost World
by Ryan Castledine
- Price$9.99
- Rating5.0
- Reviews1
-
Life Before The Flood: A Definitive Guide to the Lost World
by Ryan Castledine
- Price$22.99
- Rating4.1
- Reviews82
- Published2026-04
-
Ruined Earth: A Definitive Guide to the Lost World
by Ryan Castledine
- Price$9.99
- Rating5.0
- Reviews1
-
Ruined Earth: A Definitive Guide to the Lost World
by Ryan Castledine
- Price$34.99
- Rating5.0
- Reviews1
- Published2026-10
Main categories
FAQ
How many books does Ryan Castledine have on Amazon?
KDPTop tracks 6 of their books; 4 made an Amazon list in the last 30 days.
Which categories does Ryan Castledine publish in?
Their books chart most often in Ancient Civilizations, Civilization & Culture, World.
How does Ryan Castledine price their books?
The median price is $22.99; half of the books cost $13.24–$31.99.
Has Ryan Castledine released new books recently?
4 new books in the last 30 days, 3 of which reached a Best Sellers list.
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.