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Barbara J Barker: Amazon KDP author data
Barbara J Barker has 69 books on Amazon, 9 of them on a best-seller list in the last 30 days (best rank #1), mostly in Earth Sciences, Earthquakes & Volcanoes, Nature & Ecology.
69Books on Amazon
9Listed in 30 days
4.5Average rating
| Median price | $4.99 |
|---|---|
| Price range (middle 50%) | $4.99 – $4.99 |
| Median reviews | 316 |
| Total reviews | 6,128 |
| New books (30 days) | 1 |
| Breakout books (30 days) | 1 |
What stands out
- Only 13% of the catalog charted in the last 30 days; sales rest on a few titles.
- Median price $4.99, 32% below the median of their main category, Earth Sciences.
Barbara J Barker's best-ranked books
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INFLECTION POINT: AN APOCALYPTIC THRILLER (RING OF FIRE SERIES Book 1)
by Barbara J Barker
- Price$4.99
- Rating4.6
- Reviews578
-
Continental Breach: Ring of Fire Series Book 3
by Barbara J Barker
- Price$4.99
- Rating4.6
- Reviews182
- Published2026-09
-
Megathrust: Ring of Fire Series
by Barbara J Barker
- Price$4.99
- Rating4.6
- Reviews316
-
WRECKAGE ROAD: AN APOCALYPTIC THRILLER! (THE WRECKAGE SERIES Book 1)
by Barbara J Barker
- Price$4.99
- Rating4.5
- Reviews1,637
-
WRECKAGE RIVER: AN APOCALYPTIC THRILLER! (THE WRECKAGE SERIES Book 2)
by Barbara J Barker
- Price$4.99
- Rating4.6
- Reviews879
-
WRECKAGE RIDGE: AN APOCALYTIC THRILLER! (THE WRECKAGE SERIES Book 3)
by Barbara J Barker
- Price$4.99
- Rating4.6
- Reviews536
-
PROJECT HYPERCANE: GALVESTON: AN APOCALYPTIC DISASTER THRILLER!
by Barbara J Barker
- Price$4.99
- Rating4.7
- Reviews104
-
WRECKAGE SERIES: AN APOCALYPTIC THRILLER!
by Barbara J Barker
- Price$9.99
- Rating4.6
- Reviews30
-
WRECKAGE SERIES: AN APOCALYPTIC THRILLER!
by Barbara J Barker
- Price$14.99
- Rating4.6
- Reviews30
-
BROKEN EARTH: DEVASTATION
by Barbara J Barker
- Price$0
- Rating4.4
- Reviews756
- Published2024-04
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.