KDP categories · Top KDP authors
System Theory (Physics, Books): Amazon KDP category data
Amazon Books Best Sellers data for System Theory (Physics, Books), updated Nov 3, 2026: median price $30.70, median 34 reviews, average rating 4.4 and a KDPTop opportunity score of 34/100 (highly competitive).
| Price range (middle 50%) | $15.55 – $61.13 |
|---|---|
| Average rating | 4.4 |
| New releases (90 days) | 6% |
| Books on the list | 100 |
| Store | Books |
What stands out
- Its median reviews are 2% of the parent category Physics (1,850), one of the easier corners under it.
- The same niche in Kindle eBooks scores 22, 12 points lower than here.
- At $30.70 its median price beats 89% of Books categories, leaving more margin per copy.
Top 10 System Theory best sellers
-
Thinking in Systems: A Primer
- List rank#1
- Price$14.95
- Rating4.6
- Reviews6,548
-
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Scientific American September 2026
- List rank#3
- Price$6.99
- Rating4.8
- Reviews13
-
Scientific American October 2026
- List rank#4
- Price$6.99
- Rating4.2
- Reviews7
-
Scientific American June 2026
- List rank#5
- Price$6.99
- Rating4.4
- Reviews42
-
Systems Thinking for Work: How Leaders, Managers, and Professionals Solve Complex Problems, Avoid Costly Mistakes, and Make Smarter Decisions. (The Systems Thinker Series Book 8)
- List rank#6
- Price$4.99
- Rating5.0
- Reviews3
-
Scientific American November 2026
- List rank#7
- Price$6.99
- Reviews-
-
Complexity: A Guided Tour
by Melanie Mitchell
- List rank#8
- Price$17.99
- Rating4.5
- Reviews732
-
The Entropy Trap: What Physics Knows that Markets Don't
by Mickey M Maini
- List rank#9
- Price$9.99
- Rating4.7
- Reviews82
-
The Systems Thinker: Analytical Skills: Level Up Your Decision Making, Problem Solving, and Deduction Skills. Notice the Details Others Miss.
- List rank#10
- Price$9.67
- Rating4.1
- Reviews265
Same niche in Kindle eBooks: System Theory
FAQ
Is System Theory a good niche for Amazon KDP?
Its KDPTop opportunity score is 34/100, which makes it highly competitive. The median best seller has 34 reviews and sells for $30.70.
How many reviews do you need to rank in System Theory?
The median best seller has 34 reviews, and 74% of them have fewer than 100.
What do System Theory best sellers cost?
The median price is $30.70; half of the best sellers are priced between $15.55 and $61.13.
Can new books break into System Theory?
6% 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.