If you want a numerical readout, you can buy home water hardness test strips at any hardware store or online for under ten dollars. They work just like pool test strips—dip, wait, and compare colors.
The chart usually shows grains per gallon (gpg). Zero to 1 gpg is soft, 1–3.5 is moderately hard, and anything above 7 gpg is very hard—think “might need a dedicated water softener.”
Fun cultural note: in parts of the American Southwest, water hardness often hits 20+ gpg. Residents there joke that you could use their tap water to chisel a sculpture.
How to test household water hardness levels accurately | Cleaner-Kenya
