Protein chemistry

Isoelectric point calculator

The calculator uses the pK-value charge model described by Lukasz Kozlowski. It scans pH values from 0 upward in steps of 0.001 and reports the first value at which the calculated net charge is zero or negative.

Protein sequence

Charge profile

C-terminal pK

Asp (D) pK

Glu (E) pK

Cys (C) pK

Tyr (Y) pK

His (H) pK

Lys (K) pK

Arg (R) pK

N-terminal pK

Number of C-terminal charges

Number of N-terminal charges

Highlighted counts contribute directly to the formula.