How to use the protein molecular weight from residues calculator
Estimate protein mass from amino acid count. Enter number of amino acids in the field above; the molecular weight, molecular weight, coding dna length are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- n — Number of amino acids
Worked example
With number of amino acids = 350, the calculator gives molecular weight ≈ 38.5 kDa; molecular weight ≈ 38,500 g/mol; coding dna length ≈ 1,053 bp.
Frequently asked questions
What is the formula for the protein molecular weight from residues calculation?
Molecular weight (kDa) = n × 110 / 1000. Molecular weight (g/mol) = [Molecular weight] × 1000. Coding DNA length (bp) = 3 × n+3. Here n is number of amino acids.
What inputs do I need for the protein molecular weight from residues calculator?
You need number of amino acids. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.