How It Works
This calculator works in 4 steps.
Enter the stock % w/v
Type the percent on the stock label.
Enter the target % w/v
Type the working percent.
Enter the final volume
Type the total volume in mL or L.
Read the stock volume
The calculator returns V₁ and the grams of solute in the final volume.
The Formula
The formula applies C₁V₁ = C₂V₂ with % w/v as the concentration unit.
%₁ × V₁ = %₂ × V₂% w/v = (g solute / mL solution) × 1001% w/v = 10 g/L = 10 mg/mL- %₁ / %₂:
- Stock and target % w/v
- V₁ / V₂:
- Stock and final volumes
To make 250 mL of 5% w/v glucose from 20% w/v stock, V₁ = 5 × 250 / 20 = 62.5 mL. The final solution holds 12.5 g glucose.
Conversion Table
The conversion table lists stock volumes and g/L equivalents for 6 % w/v dilutions.
| Stock | Target | Target (g/L) | Final volume | Stock volume |
|---|---|---|---|---|
| 10% w/v | 1% w/v | 10 g/L | 100 mL | 10 mL |
| 20% w/v | 5% w/v | 50 g/L | 250 mL | 62.5 mL |
| 50% w/v | 0.9% w/v | 9 g/L | 500 mL | 9 mL |
| 5% w/v | 0.5% w/v | 5 g/L | 1,000 mL | 100 mL |
| 30% w/v | 3% w/v | 30 g/L | 200 mL | 20 mL |
| 2% w/v | 0.1% w/v | 1 g/L | 50 mL | 2.5 mL |
What Is the Weight/Volume Percent Dilution Calculator?
The Weight/Volume Percent Dilution Calculator is a tool that dilutes solutions expressed as grams of solute per 100 mL of solution (% w/v). A 10% w/v solution holds 10 g of solute in every 100 mL, which equals 100 g/L or 100 mg/mL.
% w/v is common in pharmacy, microbiology media, and biology buffers, such as 0.9% w/v sodium chloride (normal saline) and 10% w/v sodium dodecyl sulfate (SDS). The calculator returns the stock volume and states the g/L and mg/mL equivalents of each percent.
Common Uses
There are 5 main uses of this calculator.
Saline preparation
Labs dilute 10% w/v NaCl to 0.9% w/v normal saline.
Detergent stocks
Biochemists dilute 10% SDS or 10% Triton X-100 to 0.1% working levels.
Gel and stain components
Users dilute 10% ammonium persulfate (APS) for gel casting.
Media supplements
Microbiologists dilute 20% w/v sugar stocks into broth.
Pharmacy solutions
Pharmacists dilute topical and oral solutions labeled in % w/v.