Water Hardness Calculator

Calculates the hardness of water from the mineral contents of water.

Mineral content is displayed on the water bottles commercially available.
Water Hardness
Calcium content Ca2+
    1. mg/L grain/gallon
Magnesium content Mg2+

    2. mg/L
    3. of CaCO3
    2. grain/gallon
The water hardness is using American degree equivalent to mg/L.
Water hardness(mg/L)=Ca(mg/L)×2.497 + Mg(mg/L)×4.118

Classification of hard water and soft water is based on WQA (Water Quality Asociation).

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