Water hardness

Calculates water hardness from Ca and Mg concentrations in mg/l, including mmol/l, mg/l as CaCO₃, °dH and a qualitative classification (very soft/soft/moderately hard/hard/very hard).

Water hardness

This calculator computes water hardness from Ca and Mg concentrations in mg/l. It provides hardness in mmol/l, converts it to mg/l as CaCO₃ and German degrees °dH, and gives a qualitative hardness class.

Ca²⁺ [mg/l]

Mg²⁺ [mg/l]

Hardness from Ca [mmol/l] / Hardness from Mg [mmol/l]

Hardness from Ca [mmol/l]: –

Hardness from Mg [mmol/l]: –

Total hardness

Total hardness H [mmol/l]: –

Hardness as CaCO₃ [mg/l]: –

Hardness [°dH]: –

Qualitative class

Water is: –

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