Free lab calculators for authors and students: molarity and dilution (C₁V₁ = C₂V₂), concentration unit conversion (M, mM, g/L, mg/L, ppm, ppb, % w/v) and solution preparation. Enter a chemical formula to get its molecular weight automatically.
Your compound
Enter a chemical formula (e.g. NaCl, CuSO4·5H2O, Ca(NO3)2) or type the molecular weight directly. It is used by all the calculators below.
1. Molarity & Dilution Calculator
Molarity from mass
Dilution (C₁V₁ = C₂V₂)
Fill in any three boxes and leave one empty. Use the same concentration unit for C₁ and C₂.
g/L ↔ mol/L
2. Concentration Unit Converter
Converts between molar and mass units. Conversions between molar and mass units need the molecular weight above.
ppm, ppb and % w/v assume a dilute aqueous solution (density 1 g/mL): 1 ppm = 1 mg/L, 1 ppb = 1 µg/L, 1% w/v = 10 g/L.
3. Solution Preparation Calculator
How much solid to weigh to make a solution of a given concentration and volume.
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