⚛Science calculator

Molarity Calculator

Solution concentration from mass, molar mass, and volume.

Enter mass of solute, molar mass and solution volume and get molarity (mol/l) and moles of solute instantly.

InMass of soluteInMolar massInSolution volumeOutMolarity (mol/L)OutMoles of soluteOutConcentration (g/L)
3 inputs3 resultsFree no signupPrivate in your browser

Molarity Calculator

Fill in the values and the answer updates as you type.

Live
1 Your numbers
g
g/mol
L
2 Your result

How the Molarity Calculator works

Moles = mass ÷ molar mass. Molarity = moles ÷ volume in liters. Example: 5.85 g of NaCl (58.44 g/mol) in 0.5 L is about 0.2 M.

Inputs and results

The Molarity Calculator takes 3 inputs and gives 3 results.

What you enter

  • Mass of solute (g) — starts at 5.85.
  • Molar mass (g/mol) — starts at 58.44.
  • Solution volume (L) — starts at 0.5.

What you get

  • Molarity (mol/L)
  • Moles of solute
  • Concentration (g/L)

Example: Molarity Calculator with the starting values

With mass of solute 5.85 g, molar mass 58.44 g/mol and solution volume 0.5 L, the calculator returns:

Example results
Molarity (mol/L)0.2002
Moles of solute0.1001
Concentration (g/L)11.7

Change any value above and the results update straight away.

Molarity Calculator FAQ

How do I use the Molarity Calculator?

Enter mass of solute, molar mass and solution volume in the fields, then read molarity (mol/l), moles of solute and concentration (g/l) in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.

What does the Molarity Calculator calculate?

Solution concentration from mass, molar mass, and volume. It returns molarity (mol/l), moles of solute and concentration (g/l) from the 3 values you provide.

What values does the Molarity Calculator start with?

It opens with mass of solute 5.85 g, molar mass 58.44 g/mol and solution volume 0.5 L so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.

Is the Molarity Calculator free and private?

Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.

Can I rely on the Molarity Calculator for important decisions?

Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm important decisions with a qualified professional. See the Disclaimer for more.