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Peptide Sequence Property Calculator
Paste a one-letter amino-acid sequence. See molecular weight, theoretical pI, net charge across pH, GRAVY hydropathy, and the 280 nm extinction coefficient, all computed from standard reference data.
Peptide Sequence Properties
Examples:
Length
15
residues
Molecular weight
1419.55
Da (average)
Isoelectric point
3.88
theoretical pI
GRAVY
-0.693
hydrophilic
Extinction 280 nm
0
M⁻¹cm⁻¹ (reduced)
Net charge at pH 7.0
-2.02
net negative
Average mass from standard residue masses (ExPASy); theoretical pI and net charge from the EMBOSS pKa set; GRAVY from Kyte and Doolittle (1982); extinction at 280 nm from Pace et al. (1995), reduced cysteines. These are computed estimates for the sequence you enter, for educational use.
Frequently asked questions
Educational use only
This calculator is provided for research and educational purposes. Outputs are derived from the values you enter. Always verify your math and consult a licensed physician before acting on any result.