Mass Percent Calculator

About this calculator

This calculator finds a solution's mass percent concentration as (mass of solute ÷ mass of solution) × 100 — a concentration unit based purely on mass, distinct from molarity (moles per litre of solution) or molality (moles per kilogram of solvent), and often the easiest to measure directly on a lab or kitchen scale since it needs no molar mass or volume conversion. It's the same measurement behind everyday labels like “5% acetic acid” on vinegar or alcohol-by-weight figures on some beverages.

Chemistry students use it as an entry point into concentration units before moving to molarity and molality; pharmacists and lab technicians use it to prepare solutions and dilutions to an exact strength; and food scientists and manufacturers use it to calculate and label ingredient concentrations by weight. Enter the solute mass and solution mass to get the percent concentration.