Free Molarity Calculator Online
Use this free molarity calculator to determine the concentration of a solution. Enter any two of molarity, moles, and volume to solve for the third. The molarity calculator also includes a dilution mode using the C1V1 = C2V2 equation for preparing diluted solutions in the lab.
Molarity Result
Enter values to calculate
How the Molarity Calculator Works
The molarity calculator uses the definition M = n / V, where M is molarity in mol/L, n is the number of moles, and V is the volume in liters. Enter any two values and the molarity calculator solves for the third instantly.
For solution preparation, you typically know the desired molarity and volume, and need to find the number of moles (and therefore grams) of solute. For example, to make 500 mL of 0.1M NaCl, you need 0.05 moles — which equals 2.92 grams of NaCl.
The dilution mode applies C1V1 = C2V2 so you can calculate how much of a stock solution to use when preparing a diluted solution. This is essential for serial dilutions, buffer preparation, and reagent dilution in the molarity calculator.
Common Solution Concentrations
Use the molarity calculator to prepare these solutions accurately.
Solution Preparation Tips
Weigh Precisely
Use an analytical balance for solutes. A 1% error in mass creates a 1% error in molarity. The molarity calculator gives exact mass targets — your scale accuracy determines the final result.
Volumetric Flask
Always dissolve the solute first, then add solvent to the final volume mark. Adding solute to a pre-measured volume changes the total volume and molarity.
Temperature
Volume changes with temperature, affecting molarity. Prepare solutions at room temperature and note the temperature for reproducibility. The molarity calculator assumes standard conditions.
Frequently Asked Questions
Disclaimer: This molarity calculator is for educational and laboratory guidance. Always follow proper lab safety protocols when preparing chemical solutions.
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