How It Works
This calculator works in 4 steps.
Enter the stock concentration
Type the value and choose g/L, mg/mL, µg/mL, mg/L, or ng/mL.
Enter the target concentration
Type the value with its unit; the unit may differ from the stock.
Enter the final volume
Type the volume in L, mL, or µL.
Read the stock volume
The calculator converts both concentrations to mg/mL, solves for V₁, and shows the DF.
The Formula
The formula keeps the solute mass constant between the stock aliquot and the final solution.
ρ₁ × V₁ = ρ₂ × V₂m = ρ₂ × V₂1 g/L = 1 mg/mL = 1,000 µg/mL- ρ₁:
- Stock mass concentration
- ρ₂:
- Target mass concentration
- V₁ / V₂:
- Stock and final volumes
- m:
- Solute mass transferred
To make 5 mL of 200 µg/mL from a 5 mg/mL stock, convert 5 mg/mL to 5,000 µg/mL. V₁ = 200 × 5 / 5,000 = 0.2 mL (200 µL).
Conversion Table
The conversion table solves 6 dilutions with mixed mass-per-volume units.
| Stock | Target | Final volume | Stock volume | DF |
|---|---|---|---|---|
| 10 mg/mL | 1 mg/mL | 10 mL | 1 mL | 10 |
| 1 g/L | 50 mg/L | 100 mL | 5 mL | 20 |
| 5 mg/mL | 200 µg/mL | 5 mL | 0.2 mL | 25 |
| 1,000 mg/L | 10 mg/L | 250 mL | 2.5 mL | 100 |
| 2 mg/mL | 0.5 µg/mL | 20 mL | 5 µL | 4,000 |
| 100 µg/mL | 25 ng/mL | 10 mL | 2.5 µL | 4,000 |
What Is the Mass Concentration Dilution Calculator?
The Mass Concentration Dilution Calculator is a tool that dilutes solutions expressed as mass of solute per volume of solution, such as g/L, mg/mL, µg/mL, and ng/mL. The calculator converts mixed mass and volume prefixes before solving C₁V₁ = C₂V₂.
Mass concentration fits substances without a single molecular weight, such as protein mixtures, polysaccharides, and plant extracts. Note that 1 g/L equals 1 mg/mL, and 1 mg/L equals 1 µg/mL. The calculator lists these equal pairs to prevent prefix errors that shift results by 1,000-fold.
Common Uses
There are 5 main uses of this calculator.
Protein solutions
Biochemists dilute mg/mL protein stocks to µg/mL assay levels.
Antibiotic stocks
Microbiologists dilute 50 mg/mL ampicillin to 100 µg/mL in agar.
Environmental standards
Analysts dilute 1,000 mg/L element standards to µg/L levels.
Extract dosing
Researchers dose plant extracts with no single molecular weight.
Food analysis
Food labs dilute mg/L sugar and acid standards.