KDP categories · Top KDP authors
Henry H Ryffel: Amazon KDP author data
As of Nov 6, 2026, Henry H Ryffel has 9 books on Amazon, 8 of them on a best-seller list in the last 30 days (best rank #1), mostly in Mechanical Engineering, Industrial Engineering, Machinery.
| Median price | $82.21 |
|---|---|
| Price range (middle 50%) | $46.62 – $153 |
| Median reviews | 42 |
| Total reviews | 1,585 |
| New listings (30 days, incl. new editions) | 0 |
| Breakout books (30 days) | 0 |
What stands out
- 89% of the catalog made a best-seller list in the last 30 days: the whole backlist sells, not one hit.
- Median price $82.21, 83% above the median of their main category, Mechanical Engineering.
Henry H Ryffel's best-ranked books
-
Machinery's Handbook: Toolbox
by Henry H Ryffel
- Price$82.21
- Rating4.7
- Reviews293
- Published2024-04
-
Machinery's Handbook Pocket Companion: Quick Access to Basic Data & More from the 32nd Edition
by Henry H Ryffel
- Price$33.30
- Rating4.6
- Reviews22
- Published2024-04
-
Machinery’s Handbook & The Guide Combo: Large Print
by Henry H Ryffel
- Price$164
- Rating5.0
- Reviews3
- Published2024-04
-
Machinery’s Handbook Guide: A Guide to Using Tables, Formulas, & More in the 32nd Edition
by Henry H Ryffel
- Price$37.89
- Rating4.7
- Reviews42
- Published2024-04
-
Machinery's Handbook & Calc Pro 2 Combo: Large Print
by Henry H Ryffel
- Price$162
- Rating5.0
- Reviews3
- Published2024-04
-
Machinery's Handbook: Toolbox
by Henry H Ryffel
- Price-
- Rating4.7
- Reviews619
- Published2016-03
-
Machinery's Handbook, 27th Edition (Toolbox Edition)
by Henry H Ryffel
- Price-
- Rating4.7
- Reviews113
- Published2004-01
-
Machinery's Handbook 25 : A Reference Book for the Mechanical Engineer, Designer, Manufacturing Engineer, Draftsman, Toolmaker, and Machinist
by Henry H Ryffel
- Price$144
- Rating4.6
- Reviews477
- Published1996-01
-
Gear Design Simplified (Volume 1)
by Henry H Ryffel
- Price$55.81
- Rating4.2
- Reviews13
- Published1984-01
Main categories
FAQ
How many books does Henry H Ryffel have on Amazon?
KDPTop tracks 9 of their books; 8 made an Amazon list in the last 30 days.
Which categories does Henry H Ryffel publish in?
Their books chart most often in Mechanical Engineering, Industrial Engineering, Machinery.
How does Henry H Ryffel price their books?
The median price is $82.21; half of the books cost $46.62–$153.
Has Henry H Ryffel released new books recently?
0 new books in the last 30 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.