Janka Wood Hardness Rating

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The Janka test measures the force required to embed a 11.28 millimeter (0.444 inch) steel ball into wood to half its diameter. This method was chosen so that the result would leave an indention 100 square millimeters in size. It is one of the best measures of the ability of a wood species to withstand denting and wear. It is also a good indicator of how hard a species is to saw or nail.

The hardness of wood usually varies with the direction of the wood grain. If testing is done on the surface of a plank, perpendicular to the grain, the test is said to be of "side hardness." Testing the cut surface of a stump would be called a test of "end hardness."

The results are stated in various ways, which can lead to confusion, especially when the name of the actual units employed is often not attached. In the United States, the measurement is in pounds-force (lbf). In Sweden it is in kilograms-force (kgf), and in Australia, either in newtons (N) or kilonewtons (kN). Sometimes the results are treated as units, e.g., "660 Janka."

A common use of Janka hardness ratings is to determine whether a species is suitable for use as flooring.

Wood Flooring Species	Janka Hardness
Ipe / Brazilian Walnut / Lapacho	3684
Cumaru / Brazilian Teak	3540
Ebony	3220
Brazilian Redwood / Paraju	3190
Angelim Pedra	3040
Bloodwood	2900
Red Mahogany, Turpentine	2697
Spotted Gum	2473
Brazilian Cherry / Jatoba	2350
Mesquite	2345
Santos Mahogany, Bocote, Cabreuva	2200
Pradoo	2170
Brushbox	2135
Karri	2030
Sydney Blue Gum	2023
Bubinga	1980
Cameron	1940
Tallowwood	1933
Merbau	1925
Amendoim	1912
Jarrah	1910
Purpleheart	1860
Goncalo Alves / Tigerwood	1850
Hickory / Pecan, Satinwood	1820
Afzelia / Doussie	1810
Bangkirai	1798
Rosewood	1780
African Padauk	1725
Blackwood	1720
Merbau	1712
Kempas	1710
Locust	1700
Highland Beech	1686
Wenge, Red Pine	1630
Tualang	1624
Zebrawood	1575
True Pine, Timborana	1570
Peroba	1557
Kambala	1540
Sapele / Sapelli	1510
Curupixa	1490
Sweet Birch	1470
Hard Maple / Sugar Maple	1450
Coffee Bean	1390
Natural Bamboo (represents one species)	1380
Australian Cypress	1375
White Oak	1360
Tasmanian Oak	1350
Ribbon Gum	1349
Ash (White)	1320
American Beech	1300
Red Oak (Northern)	1290
Caribbean Heart Pine	1280
Yellow Birch	1260
Movingui	1230
Heart Pine	1225
Carbonized Bamboo (represents one species)	1180
Cocobolo	1136
Brazilian Eucalyptus / Rose Gum	1125
Makore	1100
Boreal	1023
Black Walnut	1010
Teak	1000
Sakura	995
Black Cherry, Imbuia	950
Boire	940
Paper Birch	910
Cedar	900
Southern Yellow Pine (Longleaf)	870
Lacewood, Leopardwood	840
Parana	780
Sycamore	770
Shedua	710
Southern Yellow Pine (Loblolly and Shortleaf)	690
Douglas Fir	660
Larch	590
Chestnut	540
Hemlock	500
White Pine	420
Basswood	410
Eastern White Pine	380