Translate a DNA or RNA sequence into its protein (amino acid) sequence using the standard genetic code. Paste your sequence, choose a reading frame — including the three reverse frames — and copy the result. Everything runs in your browser; nothing is uploaded.
Standard genetic code. U is read as T; other characters are ignored. Stop codons shown as *, unknown/incomplete codons as X.
How to use the translator
- Paste your sequence (DNA or RNA; U is read as T). FASTA headers and stray characters are ignored.
- Pick a reading frame. Use +1/+2/+3 for the sense strand and −1/−2/−3 to translate the reverse complement.
- Read the protein. Amino acids are shown in single-letter code, stop codons as
*, and any incomplete or ambiguous codon asX.
Reading frames and ORFs
A DNA sequence can be read in three frames on each strand (six in total), depending on where translation starts. To find a coding region (open reading frame, ORF), look for a translation that begins with methionine (M, codon ATG) and runs to a stop codon (*) without interruption. If your expected protein appears in frame −1 to −3, the gene is encoded on the opposite strand.
The standard genetic code
Each three-base codon specifies one amino acid (or a stop). The code is degenerate — several codons can encode the same amino acid — and this tool uses the standard code (NCBI translation table 1), which covers nuclear genes in most organisms. ATG codes for methionine and usually marks the start; TAA, TAG and TGA are stops.
Common uses
- Checking that a cloned insert is in frame and free of premature stop codons.
- Predicting the protein product of a coding sequence.
- Confirming the effect of a mutation at the protein level.
- Finding which frame/strand carries an ORF before primer or construct design.
Frequently asked questions
How do I translate the reverse strand?
Choose frame −1, −2 or −3. The tool reverse-complements your sequence and translates it 5’→3′ on that strand.
What do * and X mean?
* is a stop codon; X marks an incomplete codon at the end or a codon containing a non-standard base.
Does it work for RNA?
Yes — U is automatically read as T, so mRNA sequences translate correctly.
Which genetic code is used?
The standard genetic code (NCBI translation table 1). Alternative codes (e.g. mitochondrial) are not applied.
