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Robert J Walker: Amazon KDP author data
As of Nov 6, 2026, Robert J Walker has 106 books on Amazon, 4 of them on a best-seller list in the last 30 days (best rank #26), mostly in Dystopian, Technothrillers, Science Fiction.
| Median price | $4.99 |
|---|---|
| Price range (middle 50%) | $1.17 – $4.99 |
| Median reviews | 214 |
| Total reviews | 23,206 |
| New books (30 days) | 4 |
| Breakout books (30 days) | 2 |
What stands out
- Only 4% of the catalog charted in the last 30 days; sales rest on a few titles.
- Median price $4.99, 17% below the median of their main category, Dystopian.
- 4 new books in the last 30 days, 2 of them broke into a Best Sellers list.
Robert J Walker's best-ranked books
-
The Prepper's Valley: An EMP Post Apocalypse Prepper Survival Thriller
by Robert J Walker
- Price$0.99
- Rating4.4
- Reviews40
- Published2026-10
-
The Warning Signs: An EMP Post Apocalypse Prepper Survival Thriller Boxset
by Robert J Walker
- Price$0.99
- Reviews-
-
Pieces of Her: A Riveting Kidnapping Mystery (A Riveting Kidnapping Mystery Series Book 28)
by Robert J Walker
- Price$0
- Rating4.2
- Reviews1,571
- Published2021-05
-
Small Town Secrets: A Riveting Kidnapping Mystery (A Riveting Kidnapping Mystery Series Book 27)
by Robert J Walker
- Price$0
- Rating4.2
- Reviews1,518
- Published2021-01
-
The Hidden Prepper: EMP Survival in a Powerless World
by Robert J Walker
- Price$0
- Rating4.2
- Reviews803
- Published2022-04
-
Off the Grid: EMP Survival in a Powerless World Boxset
by Robert J Walker
- Price$0
- Rating4.3
- Reviews682
- Published2021-06
-
The Last Powered City: An EMP Post Apocalypse Prepper Survival Thriller
by Robert J Walker
- Price$3.99
- Rating4.4
- Reviews665
-
The Frozen Child: A Riveting Kidnapping Mystery (A Riveting Kidnapping Mystery Series Book 34)
by Robert J Walker
- Price$0
- Rating4.1
- Reviews626
- Published2022-02
-
The Cabin: A Riveting Kidnapping Mystery (A Riveting Kidnapping Mystery Series Book 32)
by Robert J Walker
- Price$0
- Rating4.3
- Reviews603
- Published2021-11
-
EMP Ranch: EMP Survival in a Powerless World
by Robert J Walker
- Price$0
- Rating4.5
- Reviews598
- Published2020-07
Main categories
FAQ
How many books does Robert J Walker have on Amazon?
KDPTop tracks 106 of their books; 4 made an Amazon list in the last 30 days.
Which categories does Robert J Walker publish in?
Their books chart most often in Dystopian, Technothrillers, Science Fiction.
How does Robert J Walker price their books?
The median price is $4.99; half of the books cost $1.17–$4.99.
Has Robert J Walker released new books recently?
4 new books in the last 30 days, 2 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.