๐งซEmpirical Formula Calculator
Find the empirical and molecular formula of a compound from percent composition or mass data, with full step-by-step mole-ratio working.
Free Empirical Formula Calculator
Trying to work out a compound's empirical formula from lab data? Our free empirical formula calculator does the mole-ratio math for you. Enter either the percent composition or the raw mass of each element, and it converts everything to moles, divides by the smallest value, and simplifies to the lowest whole-number ratio โ showing every step along the way.
It handles the tricky parts too: when ratios don't land on whole numbers, it explains the multiplication step needed to clear them, instead of just rounding and hoping for the best. If you know the compound's molecular molar mass, it will also derive the full molecular formula from your empirical result.
Built for chemistry students checking homework or verifying lab calculations, it runs entirely in your browser. No sign-up, no downloads. See the About page or the FAQ for more.