Janka hardness chart by species
Side hardness in pounds-force, with density and stiffness alongside it, for the species a shop actually buys. Harder resists denting; stiffer sags less over a span — they are not the same thing.
| Species | Janka (lbf) | Density (lb/ft³) | Stiffness (psi) |
|---|---|---|---|
| Hickory | 1820 | 51 | 2.16 million |
| Hard maple | 1450 | 44 | 1.83 million |
| Sapele | 1410 | 42 | 1.75 million |
| White oak | 1360 | 47 | 1.78 million |
| Ash | 1320 | 42 | 1.74 million |
| Red oak | 1290 | 44 | 1.82 million |
| Walnut | 1010 | 38 | 1.68 million |
| Soft maple | 950 | 38 | 1.64 million |
| Cherry | 950 | 35 | 1.49 million |
| Mahogany | 900 | 37 | 1.50 million |
| Douglas fir | 660 | 34 | 1.95 million |
| Poplar | 540 | 29 | 1.58 million |
| White pine | 380 | 25 | 1.24 million |
| Cedar | 350 | 23 | 1.11 million |
Reading it
- Janka measures the force to embed a steel ball halfway into the side grain. It predicts denting, not scratching and not wear through a finish.
- Density is at about 8% moisture content, which is a house in service rather than a board off the saw.
- These are species averages from the USDA Wood Handbook. They are a good bet across a stack of boards and no promise about any one of them.
Sources: Wood Handbook: Wood as an Engineering Material (FPL-GTR-282, 2021), USDA Forest Service, Forest Products Laboratory.
For the case this table does not cover
- Weight calculator
What a board or a stack of sheet goods weighs — for shelf brackets, a car boot, or a freight quote.
- Shelf sag and span
How far a shelf bends under books, how far it can span, and what a strip on the front edge buys you.