G/mol to kDa Calculator

| Added in Chemistry

What is G/mol to kDa and Why Should You Care?

G/mol (grams per mole) and kDa (kilodaltons) are both units for measuring molecular weight. While g/mol is standard in chemistry, kDa is commonly used in biochemistry and molecular biology for proteins and other macromolecules.

Understanding this conversion is essential for interpreting scientific literature, comparing molecular sizes, and working with protein data.

How to Calculate G/mol to kDa

The conversion formula is simple:

[\text{kDa} = \frac{\text{g/mol}}{1000}]

Where:

  • kDa is the molecular weight in kilodaltons
  • g/mol is the molecular weight in grams per mole

Calculation Example

Given: A protein with molecular weight of 66,500 g/mol

Calculation:

[\text{kDa} = \frac{66{,}500}{1000} = 66.5 \text{ kDa}]

This is approximately the size of bovine serum albumin (BSA).

Common Protein Sizes

Protein g/mol kDa
Insulin 5,808 5.8
Myoglobin 17,000 17
Albumin 66,500 66.5
IgG Antibody 150,000 150
Apoferritin 443,000 443

Frequently Asked Questions

A kilodalton is a unit of molecular mass equal to 1000 daltons. One dalton is approximately equal to one gram per mole. It is commonly used to express the mass of proteins and other large biomolecules.

Kilodaltons provide more convenient numbers for large molecules. A protein of 50,000 g/mol is more easily expressed as 50 kDa, making comparisons and communication simpler in biochemistry.

Small proteins are around 5-20 kDa, medium proteins 20-100 kDa, and large proteins or protein complexes can exceed 100 kDa. Antibodies are typically about 150 kDa.

For practical purposes, 1 kDa equals 1000 g/mol (or 1000 Da). The slight difference between atomic mass units and grams per mole is negligible for biological applications.