The Janka wood hardness rating scale is determined by the Janka hardness test. The Janka hardness test measures the resistance of a sample of wood to denting and wear. It measures the force required to embed an 11.28 millimeters (0.444 in) diameter steel ball halfway into a sample of wood. This method leaves a hemispherical indentation with an area of 100 mm2. (Wikipedia, n.d.)

With the Janka wood hardness scale in mind, the higher the number, the more resistant the wood is to denting and wear. For reference, when comparing two types of wood like Hickory and Chestnut, Hickory has a Janka wood hardness rating of 1820 while Chestnut has a rating of 540, therefore, from this scenario, we can conclude that Hickory is the more resistant wood. The Janka rating is also a good indication of how hard the wood will be to saw or nail.

Depending on what you are looking to use the materials for, each kind of wood has its own unique qualities. The Janka wood hardness scale has become an industry guide to deciding whether the wood is suitable for flooring. Red Oak has a Janka hardness rating of 1290, this species has become a benchmark for comparing different wood species and their relative hardness.

If you perhaps are looking to add wood flooring to a high traffic area such as a commercial space, then something with a higher Janka rating, like a White Oak might be perfect for you. If you choose a higher rated wood, you can rest assured that your wood flooring will stand the test of time and be durable enough to withstand the wear and tear of people coming and going for many years to come.

If you want to add warmth and style to a lower traffic area such as your bedroom, where the issue of wear is a lower concern, than a lower Janka rated wood, like a Walnut, could be a viable option for your wood flooring needs.

All wood will eventually wear or dent, no matter the Janka rating, with time and impact. Choosing a wood flooring option with a higher rating will lessen the effects and lengthen the longevity of the wood.