Enter your protein sequence below (numbers, spaces, and punctuation will be removed).  When you press Submit, a new window will appear with your hydropathy plot results.

You can change the window size to adjust the number of amino acids that are averaged to obtain the hydropathy score at each position.  Your window size can drastically change the appearance of the resulting graph and the predictions you make about protein structure.  To learn how to use the window size effectively click here.  If you leave this entry blank, a window size of 9 will be used.

You can also zoom in on a section of your protein by entering a range of amino acids you wish to analyze. You may enter a starting and/or ending position, and your hydropathy plot will be scaled accordingly.  If you leave these entries blank, the entire protein will be analyzed.

Enter your amino acid sequence below:




Window size


Start Position


End Position

Protein Length

Background Info


A list of all the individual amino acid hydropathy scores: Amino Acid Hydropathy Scores


Kyte, J. and Doolittle, R. 1982. A simple method for displaying the hydropathic character of a protein. J. Mol. Biol. 157: 105-132.

This web page was created by Soren Johnson, Rachel Patton McCord and Lisa Robinson, and modified by Laurie Heyer.