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+
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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    Water Hardness
    [1-10] /18Disp-Num
    [1]  2021/12/02 04:34   30 years old level / An engineer / Very /
    Purpose of use
    Checking other software's calculation of hardness. They match with your calculator.
    [2]  2021/05/13 17:39   40 years old level / Others / Very /
    Purpose of use
    Double check calculations.
    [3]  2020/03/09 17:49   40 years old level / A teacher / A researcher / Very /
    Purpose of use
    Assess the specifications of a RO system with remineralization.
    Please also add other minerals like Na+, K+ and the alkalinity / pH calculation.
    Thank you!
    [4]  2019/10/10 17:43   20 years old level / High-school/ University/ Grad student / A little /
    Purpose of use
    Trying to understand how hardness is calculated for an environmental engineering course
    [5]  2019/07/15 02:16   20 years old level / Elementary school/ Junior high-school student / Very /
    Purpose of use
    make solution
    [6]  2019/01/07 14:13   50 years old level / Others / Very /
    Purpose of use
    calculate hardness of water to help a citizen
    [7]  2018/10/12 02:01   50 years old level / High-school/ University/ Grad student / Useful /
    Purpose of use
    Water softener setting....
    [8]  2018/06/15 17:25   60 years old level or over / An engineer / Very /
    Purpose of use
    Design of a process
    [9]  2017/03/01 20:40   50 years old level / Others / Very /
    Purpose of use
    To calculate farm well-water hardness from mineral analysis done on the water to aid in determining buffering needs for herbicide applications.
    [10]  2017/03/01 09:27   40 years old level / Self-employed people / Very /
    Purpose of use
    Mg (mg/l)x4.118
    4.118 means


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