6 units · base unit mg/L CaCO₃ · M L⁻³
Household water hardness converter
Water hardness is normally reported as an equivalent concentration of calcium carbonate. The regional degree scales are conventions, not different substances.
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Show this value in all 6 household water hardness units
- Milligram per litre as CaCO3s mg/L CaCO₃ 1
- Part per million as CaCO3s ppm CaCO₃ 1
- French degrees °fH 0.1
- German degrees °dH 0.056 028 686 687 6
- English or Clark degrees °e 0.070 155 745 755 6
- Grain per US gallons gpg 0.058 417 831 164 1
Every row is Milligram per litre as CaCO3 (mg/L CaCO₃) converted through the mg per liter caco3, in exact rational arithmetic.
Common household water hardness conversions
- mg/L CaCO₃ → ppm CaCO₃
- mg/L CaCO₃ → °fH
- mg/L CaCO₃ → °dH
- mg/L CaCO₃ → gpg
- ppm CaCO₃ → mg/L CaCO₃
- ppm CaCO₃ → °fH
- ppm CaCO₃ → °dH
- ppm CaCO₃ → gpg
- °fH → mg/L CaCO₃
- °fH → ppm CaCO₃
- °fH → °dH
- °fH → gpg
- °dH → mg/L CaCO₃
- °dH → ppm CaCO₃
- °dH → °fH
- °dH → gpg
- gpg → mg/L CaCO₃
- gpg → ppm CaCO₃
- gpg → °fH
- gpg → °dH
All household water hardness units
Each unit expressed in milligram per litre as caco3s (mg/L CaCO₃), the unit everything in this category converts through.
| Unit | Symbol | System | Value in mg/L CaCO₃ |
|---|---|---|---|
| Milligram per litre as CaCO3 | mg/L CaCO₃ | metric | 1 |
| Part per million as CaCO3 | ppm CaCO₃ | other | 1 |
| French degree | °fH | historic | 10 |
| German degree | °dH | historic | 17.848 |
| English or Clark degree | °e | historic | 14.254 |
| Grain per US gallon | gpg | us | 17.1180610453 |
About household water hardness units
Convert household water-hardness conventions used by kettles, dishwashers, aquariums and test strips.
Water hardness is normally reported as an equivalent concentration of calcium carbonate. The regional degree scales are conventions, not different substances.
Dimensional formula: M L⁻³. Every conversion on this page goes through the milligram per litre as caco3, using exact fractions rather than decimal approximations. Read how that works →