Empirical Formula Calculator

Convert element amounts to mole ratios, scale them toward small whole-number subscripts, and show when the fit is uncertain.

Use masses or percentages consistently. Atomic weights are taken from the bundled periodic-table data.

—Whole-number ratios are not forced when the data fit is poor.

Empirical → molecular formula bridge

Use an empirical formula and measured molar mass to solve the integer multiplier and molecular formula, with a tolerance warning when the ratio is not close to an integer.

Empirical formulaMeasured molar mass (g/mol)

—Empirical formula mass

—Multiplier n

—Molecular formula

Ready.

From composition to the simplest ratio

Percent or mass data are converted to moles for each element, then divided by the smallest mole amount. Ratios close to fractions such as 1.5 or 1.333 may need multiplication to reach whole-number subscripts. Experimental composition data can require judgment because measurement error prevents perfectly exact ratios.