Molarity Converter

Convert molar concentration between M, mM, µM, nM, pM, fM, and aM laboratory scales.

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.

Use decimals or scientific notation.
UnitSymbolEquivalenceValueAmount in 1 µL
molarM1 M1e-6
millimolarmM10⁻³ M0.001
micromolarµM10⁻⁶ M11 pmol
nanomolarnM10⁻⁹ M1000
picomolarpM10⁻¹² M1e6
femtomolarfM10⁻¹⁵ M1e9
attomolaraM10⁻¹⁸ M1e12
Method: convert the input to the base unit first, then convert from that base unit to each target unit. The base unit is molar (M).

Molar concentration conversions for laboratory work

This converter is useful when comparing stock solutions, protocols, assay conditions, and instrument results reported at different concentration scales.

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.