Reverse Complement
Get the reverse complement of one or many DNA sequences, with IUPAC ambiguity codes handled correctly.
What is a reverse complement?
DNA is double-stranded: each strand is the reverse complement of the other. Given
ATGGC on one strand, the opposite strand reads GCCAT in the
5′→3′ direction. The reverse complement operation flips the sequence and swaps every base
for its partner (A↔T, G↔C).
Where it is used
- Designing reverse PCR primers
- Checking whether a read maps to the forward or reverse strand
- Analysing genes on the minus strand of a genome
IUPAC ambiguity codes
Ambiguous bases are complemented correctly: R (A/G) ↔ Y (C/T), K (G/T) ↔ M (A/C), S ↔ S, W ↔ W, B ↔ V, D ↔ H, and N stays N.
Frequently asked questions
Does it reverse, complement, or both?
Both — that is the definition of a reverse complement. If you only need the complement, run the tool and reverse the result, or use a sequence editor.