Compound Formula Calculator

Find the molecular formula from masses.

About Compound Formula Calculator

The molecular formula for Compound Formula is found by dividing the molecular mass by the empirical formula mass to get the number of formula units, and the mole count follows from mass over molar mass. Many compounds share an empirical formula, so the molecular mass is what picks the actual one.

Formula

Compound Formula

Multiplier = molecular mass / empirical formula mass

molecular formula: Empirical formula repeated n times

Worked example

With the default values below, Compound Formula Calculator returns Formula Multiplier of 3.00. Change any input above and every figure here is recalculated in your browser.

Inputs used

Empirical formula massminimum 0 g/mol: 30 g/mol
Molecular massminimum 0 g/mol: 90 g/mol
Compound massminimum 0 g: 45 g

Results

Formula Multiplier: 3.00
Moles of Compound: 0.500 mol
Molecules: 301,100,000,000,000,000,000,000

Step by step

1Values used
2Compound Formula
3Formula Multiplier= 3.00
4Moles of Compound= 0.500 mol
5Molecules= 301,100,000,000,000,000,000,000

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax or fees or charges into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is Compound Formula calculated?

Multiplier = molecular mass / empirical formula mass The molecular formula for Compound Formula is found by dividing the molecular mass by the empirical formula mass to get the number of formula units, and the mole count follows from mass over molar mass.

Why does Compound Formula matter?

Many compounds share an empirical formula, so the molecular mass is what picks the actual one.

What values do I need to enter?

This calculator takes 3 inputs: Empirical formula mass, Molecular mass, Compound mass. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.