Random Sequence
How to generate a random DNA or protein sequence
- Choose DNA or protein, then set the length and the number of sequences, and for DNA the GC content.
- Click Generate.
- Each sequence is a FASTA record. Copy output or Download saves the result.
Frequently asked questions
How random is it?
It uses the browser's cryptographic random number generator. Each base is drawn on its own, so the GC content is close to what you set but varies a little between sequences.
What is GC content?
The share of bases that are G or C. Genomes range widely: the human genome is about 41% GC, and some bacteria are below 30% or above 70%.
Does it start with methionine?
No. Every position is drawn at random. Use Random Coding DNA if you want a start codon.
What are random proteins used for?
As controls for alignments, motif searches and prediction tools: a real hit should score better than random sequences of the same length.
Are the sequences stored anywhere?
No. They are made in your browser and are gone when you close the page, unless you copy or download them.