The molecular weight (mw) of an oligopeptide or a protein can be determined by summation of the mw of its corresponding amino acid sequence. Certain modifications to this sequences can result in changes to the mw. This calculator provides the mw of an unmodified oligopeptide or protein.
The extinction coefficient of a oligopeptide or protein can also be calculated given its sequence. This value is useful for determining the concentration of a peptide or protein solution.
MLA | "Quest Calculate™ Peptide and Protein Molecular Weight Calculator." AAT Bioquest, Inc., 19 Oct. 2025, https://www.aatbio.com/tools/calculate-peptide-and-protein-molecular-weight-mw. | |
APA | AAT Bioquest, Inc. (2025, October 19). Quest Calculate™ Peptide and Protein Molecular Weight Calculator. AAT Bioquest. https://www.aatbio.com/tools/calculate-peptide-and-protein-molecular-weight-mw. | |
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