It is a white extremely hygroscopic solid that is soluble in water, alcohols, and other polar organic solvents.

[6] It is one of the few strong acids that is solid and therefore is conveniently weighed and stored.

Impurities can be removed by recrystallization from its concentrated aqueous solution followed by azeotropic drying with toluene.

[2] TsOH finds use in organic synthesis as an "organic-soluble" strong acid.

These reactions are usually performed in an aprotic solvent, often pyridine, which additionally acts as a base.