Janka Hardness Ratings
The Janka Hardness test measures the hardness of wood and is typically referred to in comparing the hardness of wood flooring types. This test measures the force required to embed an 11.28mm (0.444 in) steel ball to half its depth into wood.
The Janka Hardness test is the industry standard for determining the ability of a particular timber species to withstand denting and wear.
While the Janka Hardness rating helps to classify woods based upon hardness and density, it can also be a good indication of how much wear and tear a particular wood can withstand. The woods in the upper portion of the Janka Scale, such as 12 and higher tend to resist denting more than softer woods with a rating of 6 and under. The Janka rating can also help determine how difficult a particular wood will be to saw or nail.
The higher the Janka rating / number the greater the hardness.