KDP categories · Top KDP authors
Hard Science Fiction (Science Fiction, Kindle eBooks): Amazon KDP category data
Amazon Kindle eBooks Best Sellers data for Hard Science Fiction (Science Fiction, Kindle eBooks), updated Nov 2, 2026: median price $9.49, median 8,592 reviews, average rating 4.5 and a KDPTop opportunity score of 21/100 (highly competitive).
| Price range (middle 50%) | $4.99 – $11.99 |
|---|---|
| Average rating | 4.5 |
| New releases (90 days) | 14% |
| Books on the list | 100 |
| Store | Kindle eBooks |
What stands out
- Its review barrier is higher than in 99% of Kindle eBooks categories: the median best seller has 8,592 reviews, so new books need time to build up.
- Prices spread wide: the middle half runs from $4.99 to $11.99, so budget editions and premium or boxed sets sell side by side.
Top 10 Hard Science Fiction best sellers
-
-
Morning Star (Red Rising Series Book 3)
by Pierce Brown
- List rank#2
- Price$12.99
- Rating4.7
- Reviews62,292
-
-
The Caves of Steel (The Robot Series Book 1)
by Isaac Asimov
- List rank#4
- Price$2.99
- Rating4.5
- Reviews11,552
-
Engineer of the Exotic (The Saucer Series Book 1)
- List rank#5
- Price$2.99
- Rating4.4
- Reviews802
-
Anvil of Stars (Forge of God Book 2)
by Greg Bear
- List rank#6
- Price$1.99
- Rating4.3
- Reviews1,445
-
We Are Legion (We Are Bob) (Bobiverse Book 1)
by Dennis Taylor
- List rank#7
- Price$9.99
- Rating4.5
- Reviews35,050
-
Children of Time
- List rank#8
- Price$9.99
- Rating4.5
- Reviews51,769
-
-
Tavalai Rebellion: (The Spiral Wars Book 11)
by Joel Shepherd
- List rank#10
- Price$5.99
- Rating4.7
- Reviews18
Same niche in Books: Hard Science Fiction
FAQ
Is Hard Science Fiction a good niche for Amazon KDP?
Its KDPTop opportunity score is 21/100, which makes it highly competitive. The median best seller has 8,592 reviews and sells for $9.49.
How many reviews do you need to rank in Hard Science Fiction?
The median best seller has 8,592 reviews, and 11% of them have fewer than 100.
What do Hard Science Fiction best sellers cost?
The median price is $9.49; half of the best sellers are priced between $4.99 and $11.99.
Can new books break into Hard Science Fiction?
14% of the current best sellers were released in the last 90 days.
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.