Frequency of nucleotides and oligonucleotides in a sequence

This demo is limited to oligos 1-3 bases long, and a maximum input sequence of 10000 bp.
Copy your sequence in the textarea below
(non coding characters, as number, returns or spaces will be removed)

Select length of oligonucleotides *
Compute frequencies in

This version does not work with degenerated nucleotides
* when selected length is one, frequency of nucleotides A, C, G and T will be reported.

Source code is freely downloable at