Peptide molecular weight and CAS number chart

The chart

Molecular weights are average molecular weights in g/mol. Each name links to the compound’s page, and each CAS number to the record it was checked against.

Source: PubChem (National Library of Medicine), retrieved 2026-10-10. Each entry matched by exact synonym and checked against an independent molecular weight within 1%. Two compounds PubChem holds without a computed record are given from their published formula, with the weight computed from it..

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Using molecular weight at the bench

A balance measures mass, and an assay is usually specified in moles. Molecular weight is the bridge: moles = mass ÷ molecular weight. A 10 mg vial of a peptide with a molecular weight of 1,000 g/mol holds 10 µmol, and dissolved in 1 mL it is a 10 mM solution.

The peptide reconstitution calculator does this for any peptide on the chart: concentration in mg/mL, the same in µM, and the volumes for diluting to a working concentration.

What the chart leaves out

Blends and compounds without a single defined structure are not listed: a mixture has no one molecular weight. A figure that could not be checked against a second reference was left out, since a wrong number on a reference chart is worse than a gap. Storage guidance for lyophilized material is on the storage and handling page.