Sequence
Translate and ORFs
Translate a nucleotide sequence in all six reading frames using four genetic code tables, and find open reading frames with optional alternative start codons.
Input sequence
Six-frame translation
Open reading frames
No ORF found with these settings. Try a shorter minimum length.
Formula
three nucleotides = one codon = one amino acid
- forward frames
- three frames on the given strand, starting at base one, two and three
- reverse frames
- the same three frames on the reverse complement
- ORF
- from a start codon to the first stop codon in the same frame
Worked example
Finding the GFP coding region in a 441 base fragment
- the sequence begins with ATG and ends with TAA
- All six frames are translated and stop codons are highlighted.
- The frame with a continuous translation and no internal stops is the coding frame.
- The tool lists that same region as an ORF.
Answer forward frame one, base 1 to 441, giving 146 amino acids plus a stop codon
Common mistakes
- Translating in the wrong frame. If the output is full of asterisks you have not found the coding frame — check the other frames and the opposite strand.
- Using the standard table on mitochondrial sequence. In vertebrate mitochondria TGA codes for tryptophan rather than stop, and AGA and AGG are stops.
- Reporting ORF length without saying whether the stop codon is counted. Here the nucleotide column includes the stop codon and the amino acid column does not.
Frequently asked
Why is the ORF length not exactly three times the amino acid count?
Because the stop codon counts toward the nucleotide length but produces no amino acid. The amino acid count is therefore the length divided by three, minus one.
What are alternative start codons?
In bacteria GTG and TTG can also start translation. Enable that option for prokaryotic sequence, otherwise you will miss a share of the genes.