The Janka Hardness Test measures the resistances a sample of wood has to denting and wear. It measures the force required to embed a 11.28mm (.444 inch) steel ball into wood up to half the ball’s diameter. This method leaves an indentation.
A common use of Janka hardness ratings is to determine if a wood species is suitable for flooring.
The harder the wood, the longer it will last under heavy use, however, harder wood also takes longer to sand and refinish.
25 Wood Species Ranked from Hardest to Softest
Learn how to maintain and protect your hardwood floor, as well as how often it should be refinished.