ppb to umol/L Converter - Parts per billion to Micromolar

Conversion derivation

Express both ppb and umol/L in the same base unit mol/L (molar), then cancel the shared base unit.

1. 1

   Rewrite ppb in the base unit

   $$1\mathrm{ppb}=1\times 10^{-9}mol/L$$
2. 2

   Rewrite umol/L in the base unit

   $$1umol/L=0.000001mol/L$$
3. 3

   Forward conversion

   $$\begin{array}{rl}1\mathrm{ppb}& =\frac{1\times 10^{-9}\cancel{mol/L}}{0.000001\cancel{mol/L}}\times 1umol/L\\ & =\frac{1\times 10^{-9}}{0.000001}umol/L\\ & =0.001umol/L\end{array}$$
4. 4

   Reverse conversion

   $$\begin{array}{rl}1umol/L& =\frac{0.000001\cancel{mol/L}}{1\times 10^{-9}\cancel{mol/L}}\times 1\mathrm{ppb}\\ & =\frac{0.000001}{1\times 10^{-9}}\mathrm{ppb}\\ & =1,000\mathrm{ppb}\end{array}$$