Kilodaltons to g/mol Converter
Common Conversions
| kDa | g/mol |
|---|---|
| 0.1 | 100 |
| 0.5 | 500 |
| 1 | 1000 |
| 5 | 5000 |
| 10 | 10000 |
| 25 | 25000 |
| 50 | 50000 |
| 66.5 | 66500 |
| 100 | 100000 |
| 150 | 150000 |
| 500 | 500000 |
| 1000 | 1000000 |
Why this conversion matters in chemistry
Molarity calculations on a protein stock use this conversion regularly. A 2 mg/mL solution of a 150 kDa antibody is 2 mg/mL ÷ 150,000 g/mol = 1.33 × 10⁻⁵ M, or 13.3 µM. The kDa figure off a Western-blot ladder or a structural-biology PDB entry expands by 1000 to give the g/mol form a molarity equation expects. The factor falls cleanly out of 1 kDa = 1000 Da and the 1 Da = 1 g/mol identity. The conversion is the everyday first step bridging a protein-scale molecular weight in biochemist's units and the per-mole arithmetic a stoichiometry or binding calculation runs in.
Formula
Worked Examples
BSA — the molar mass that anchors many quantitation calibration curves.
IgG antibody — the per-mole figure for any antibody-binding stoichiometry.
The conversion anchor — about a 9-residue peptide expressed in g/mol.
A small protein — chymotrypsin-sized, useful as a low-MW reference.