Percent Solution Calculator — w/v, w/w, v/v Concentration
Calculate how concentrated a solution is as a percentage. Choose mass/volume, mass/mass, or volume/volume mode, enter the solute and total solution amounts, and get the percentage concentration instantly.
Solution type
%(w/v) = (mass solute / volume solution) × 100
- 1
Concentration ratio
5 ÷ 100 = 0.05 - 2
Percent concentration
0.05 × 100 = 5
How does this calculator work?
Percent concentration = (solute / total solution) × 100. Choose %(w/v) for g/mL, %(w/w) for g/g, or %(v/v) for mL/mL. Example: 5 g NaCl in 100 mL solution = 5%(w/v). Always divide by total solution, not by solvent alone.
Formula
How this is calculated
Percent concentration expresses how much solute is present relative to the total solution. Three conventions exist depending on the units used: mass/volume (w/v, the most common in biology and medicine), mass/mass (w/w, standard in industrial and food chemistry), and volume/volume (v/v, used for liquid-in-liquid mixtures like alcohol in water). All divide solute by total solution — not by solvent — and multiply by 100.
For example, a 5 %(w/v) saline solution contains 5 g of NaCl dissolved in enough water to bring the final volume to 100 mL. A 70 %(v/v) ethanol solution contains 70 mL of pure ethanol made up to 100 mL with water. A 30 %(w/w) hydrogen peroxide solution contains 30 g of H₂O₂ in every 100 g of solution.
Important assumptions: the calculator computes the ratio of solute to total solution, not solute to solvent. When dissolving a solid in a liquid, the total volume changes (volume contraction or expansion), so 5 g dissolved in 100 mL of water gives a slightly different total volume than 100 mL. For precision lab work, always dissolve the solute in a volumetric flask and bring to the exact final volume with solvent.
Frequently asked questions
%(w/v) divides the mass of solute (grams) by the volume of solution (millilitres); %(w/w) divides the mass of solute (grams) by the total mass of solution (grams). For dilute aqueous solutions (where 1 mL ≈ 1 g), the two are nearly equal, but they diverge for concentrated solutions or non-aqueous solvents.
Weigh out 5 g of NaCl. Dissolve it in about 80 mL of distilled water in a 100 mL volumetric flask. Add water carefully until the meniscus reaches the 100 mL mark. This gives exactly 5 g / 100 mL = 5 %(w/v).
No. In many countries, alcohol percentage is expressed as %(v/v) at 20 °C (e.g. 40 %(v/v) vodka). "Proof" is a separate historical unit: in the US, proof = 2 × %(v/v), so 80-proof vodka is 40 %(v/v). In the UK the older proof system was different still. This calculator uses the international %(v/v) definition.
Also known as
TG we-Calculate Editorial Team. (2026). Percent Solution Calculator — w/v, w/w, v/v Concentration [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/percent-solution-calculator
TG we-Calculate Editorial Team. "Percent Solution Calculator — w/v, w/w, v/v Concentration." TG we-Calculate. 2026. https://we-calculate.com/calculator/percent-solution-calculator.
TG we-Calculate Editorial Team, "Percent Solution Calculator — w/v, w/w, v/v Concentration," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/percent-solution-calculator
@misc{wecalculate_percent_solution_calculator, title = {Percent Solution Calculator — w/v, w/w, v/v Concentration}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/percent-solution-calculator}}, year = {2026}, note = {TG we-Calculate} }
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