# The Tocris Molarity Calculator

## Calculate the mass, volume or concentration required for a solution

The Tocris molarity calculator is a useful tool which allows you to calculate the:

• mass of a compound required to prepare a solution of known volume and concentration
• volume of solution required to dissolve a compound of known mass to a desired concentration
• concentration of a solution resulting from a known mass of compound in a specific volume

### Calculate now!

Mass
=
Concentration
x
Volume
x
MW*

g/mol
*When preparing stock solutions always use the batch-specific molecular weight of the product found on the vial label and SDS / CoA (available online).
##### The molarity calculator equation

The Tocris molarity calculator is based on the following equation:

Mass (g) = Concentration (mol/L) x Volume (L) x Molecular Weight (g/mol)
##### An example of a molarity calculation using the Tocris molarity calculator

What is the mass of compound required to make a 10 mM stock solution in 10 ml of water given that the molecular weight of the compound is 197.13 g/mol?

1. Enter 197.13 into the Molecular Weight (MW) box
2. Enter 10 into the Concentration box and select the correct unit (millimolar)
3. Enter 10 into the Volume box and select the correct unit (milliliter).
4. Press calculate
5. The answer of 19.713 mg appears in the Mass box

### Molarity Calculator

#### Now mobile-optimized!

Our popular molarity calculator has now gone mobile! Try it on your smartphone today for molarity calculations on the go.