Molarity Converter
Convert molarity units between M, mM, µM, nM, pM, fM, and aM. This page is for concentration unit conversion only.
This calculator is useful when you need a quick unit check without working through each conversion factor by hand. Enter one value to compare every supported unit side by side.
Molarity Converter
Enter a concentration and choose its starting unit. The table shows the same concentration across the full molarity scale as a quick sanity check. Scientific notation such as 1e-6 is supported.
| Unit | Symbol | Conversion factor | 1 µM = | Amount in 1 µL |
|---|---|---|---|---|
| molar | M | 1 M = 1 M | 1 × 10−6M | |
| millimolar | mM | 1 mM = 0.001 M | 0.001mM | |
| micromolar | µM | 1 µM = 1 × 10−6 M | 1µM | 1 pmol |
| nanomolar | nM | 1 nM = 1 × 10−9 M | 1,000nM | |
| picomolar | pM | 1 pM = 1 × 10−12 M | 1 × 106pM | |
| femtomolar | fM | 1 fM = 1 × 10−15 M | 1 × 109fM | |
| attomolar | aM | 1 aM = 1 × 10−18 M | 1 × 1012aM |
Molarity unit conversions for laboratory work
This converter is useful when comparing stock solutions, protocols, assay conditions, and instrument results reported at different concentration scales.
Need to calculate required mass, final volume, or concentration from molar mass? Use the Solution Molarity Calculator. For protein-specific conversions using molecular weight in kDa, use the Protein Molarity Calculator.
What molarity measures
Molarity is the amount of substance per liter of solution. One molar (1 M) equals one mole per liter (1 mol/L). It describes concentration, not the total number of moles in a sample.
Example
Enter 1 mM to see that it equals 1,000 µM or 1e6 nM. A 1 µM solution contains 1 pmol of substance in each microliter.
Working with a protein solution? Use the Protein Molarity Calculator to convert between protein mass and molarity using molecular weight in kDa.