Sequence Analysis
Reverse Complement
Builds the reverse complement, complement, and reverse of a DNA/RNA sequence.
This is a sample. Click the box to start typing and it will clear.
Examples:
24 bp · GC content 54%
Detected as DNA.
Result — Reverse complement
- Length
- 24 bp
- GC content
- 54.2%
- Base counts
- A 6C 6G 7T 5
How to use it
- Paste a nucleotide sequence or FASTA, or drop a file in. Spaces, digits and line breaks are ignored.
- Choose the operation. Reverse complement is the one nearly everybody wants; reverse and complement are there because they are not the same thing.
- Copy either side. The cleaned-up input is often the thing worth keeping, so it has its own copy button.
Worth knowing
- Case is data. Lower case commonly marks a masked or low-confidence region, so the complement of a is t rather than T unless you ask for one case throughout.
- Ambiguity codes complement properly: R pairs with Y, and so on. Mapping them to N would quietly lose what you typed.
- Characters that are not nucleotides are reported rather than deleted. One missing letter shifts every position after it, which is exactly the error that survives into an ordered primer.
Questions
Reverse turns the sequence back to front. Complement swaps each base for its partner. Reverse complement does both, and it is the one that gives the other strand read in the usual direction.
Yes. Choose the alphabet, or let it decide from what you pasted.
So an aligned row can be flipped and still line up with its neighbours.
The other sequence tools
- DNA to Protein Translation — Six-frame translation and open reading frames, in any NCBI genetic code.
- Primer Tm Calculator — Melting temperature by the nearest-neighbour model
- GC Content Calculator — GC and AT content, skew, and GC along the sequence.