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Onex Peptides, Canadian research peptide supplier

Calculator

Molecular Weight Calculator

Calculate the average molecular weight of a compound from its molecular formula, with the contribution of each element.

Formula

Result

Enter a formula, or pick a compound to load the formula from its specification.

How the weight is calculated

Each element’s count is multiplied by its standard atomic weight and the products are summed. The result is the average molecular weight, the figure a specification sheet and a molar conversion use.

Average weight is not the mass-spectrum peak

A mass spectrum reports monoisotopic mass, built from the most abundant isotope of each element, and for a larger peptide the most intense peak may be neither figure. A certificate whose observed mass differs from this calculator by a few daltons is not necessarily wrong. Compare like with like.

Salt forms and hydrates weigh more per mole than the free compound. Enter the counter-ion or water after a · to include it.

All products sold by Onex Peptides are supplied strictly as reference materials for in vitro laboratory research and analytical use. They are not drugs, foods, cosmetics or medical devices, and they are not for human or veterinary use, consumption or administration of any kind.