CalcKit
Concentration Solution Converter
The mass concentration of a solution is how much of a substance is dissolved in each unit of its volume: grams per liter (g/L), milligrams per liter (mg/L), parts per million (ppm), or grains per gallon (gpg) for water hardness.
In water, 1 mg/L is 1 ppm, since a liter of water weighs a million milligrams. The converter treats them as equal, which holds for water and dilute solutions, but not for dense ones such as brines.
Molar concentrations, in mol/L, are converted in the Concentration - Molar Converter.
How to convert concentration units
Type a value into any field, and every other unit is calculated at once. For example, water hardness is often given in grains per gallon, and a hard 10 gpg (US) is:
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In mg/L, or ppm: multiply by 17.1181.
10 × 17.1181 = 171.2 mg/L -
In g/L: divide that by 1,000.
171.2 / 1,000 = 0.1712 g/L
Common conversions
| Value | Equals |
|---|---|
| 1 g/L | 1,000 mg/L |
| 1 mg/L | 1 ppm |
| 1 gpg(US) | 17.1181 mg/L |
| 1 mg/L | 0.0584178 gpg(US) |
| 1 gpg(UK) | 14.2538 mg/L |
| 1 lb/gal(US) | 119.826 g/L |
| 1 lb/ft³ | 16.0185 g/L |
Concentration units
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Kilogram per Liter (kg/l): Kilograms of solute per liter of solution. This is considered as base unit.
Conversion Factor: 1 kg/l = 1,000 g/l -
Gram per Liter (g/l): Grams of solute per liter of solution.
Conversion Factor: 1 g/l = 1,000 mg/l -
Milligram per Liter (mg/l): Milligrams of solute per liter of solution.
Conversion Factor: 1 mg/l = 1 ppm -
Part per Million (ppm): One part of solute per million parts of solution. The converter interprets this unit as one millionth of kg/l.
Conversion Factor: 1 ppm = 1 mg/l -
Grain per Gallon (gpg): Grains of solute per US gallon of solution.
Conversion Factor: 1 gpg(US) = 17.1181 mg/l; 1 gpg(UK) = 14.2538 mg/l -
Pound per Gallon (lb/gal): Pounds of solute per US gallon of solution.
Conversion Factor: 1 lb/gal(US) = 119.8264 g/l; 1 lb/gal(UK) ≈ 99.776 g/l -
Pound per Cubic Foot (lb/ft³): Pounds of solute per cubic foot of solution.
Conversion Factor: 1 lb/ft³ = 16.0185 g/l
Frequently asked questions
How do I convert a percentage to mg/L?
For a weight-per-volume percentage, 1% is 1 g per 100 mL, which is 10 g/L or 10,000 mg/L. So a 0.9% salt solution is 9 g/L.