Chemistry & Lab tools
Concentration calculator
Enter solute mass, solution amount and density once, and read off %w/w, %w/v and g/L all at the same time — no repeated conversions.
Formula
%w/w = (Solute Mass ÷ Solution Mass) × 100
%w/v = (Solute Mass ÷ Solution Volume) × 100
%w/v = (Solute Mass ÷ Solution Volume) × 100
Solution details
Solute mass
Mass of the dissolved substance
g
Total solution volume
Final volume of the prepared solution
mL
Solution density
Grams per millilitre — 1.00 for near-water solutions
g/mL
Concentration
0 g/L
%w/v–
%w/w–
mg/mL–
%w/v and g/L describe the same thing at different scales — 1% w/v is exactly 10 g/L, regardless of density, since both are defined against volume. %w/w depends on density because it’s defined against the mass of the whole solution, which is why it only equals %w/v for solutions with a density of exactly 1.00 g/mL.
Frequently asked questions
What is the difference between %w/w and %w/v?
%w/w is grams of solute per 100 grams of total solution. %w/v is grams of solute per 100 millilitres of solution. They only match exactly when density is 1 g/mL.
How do I convert %w/w to g/L?
Multiply %w/w by the solution’s density in g/mL, then by 10, since 100g of solution times density gives the volume, scaled to a full litre.
Why does solution density matter?
Density links mass-based and volume-based units. Without it, %w/w and %w/v can only be assumed equal for dilute aqueous solutions near water’s density.
Is this concentration calculator free to use?
Yes. It runs entirely in your browser, needs no account, and nothing you enter is stored or transmitted.