The Float Test
To determine the category of your hair’s porosity, take a few strands of hair from your comb or brush and drop them into a bowl of water. Let them sit for 2-4 minutes.
-Low porosity: If the strand floats at the top before sinking.
-Normal porosity: If the strand floats somewhere in the middle of the glass.
-High porosity: If the strand quickly sinks to the bottom of the glass.