What genetic code does this use?

It uses the standard genetic code, NCBI translation table 1, which applies to nuclear genes in most organisms. AUG codes for methionine and serves as start, while UAA, UAG, and UGA are stop codons. Organelle and a few alternative codes differ and are not applied here.

Does it matter if I enter DNA or RNA?

No. The tool converts thymine to uracil internally so DNA and mRNA give the same protein. The coding or sense strand of DNA reads identically to the mRNA apart from T versus U, so paste either and you get the correct translation.

What are the three reading frames?

A nucleotide sequence can be read in three frames depending on whether translation starts at the first, second, or third base. Shifting the frame regroups the triplets entirely and usually produces a different protein, so choosing the correct frame is essential.

How are stop codons shown?

Stop codons UAA, UAG, and UGA are rendered as an asterisk in the one-letter output and as the word Stop in the three-letter output. Translation continues past a stop so you can see the full reading frame, including any downstream codons.

What happens to extra bases at the end?

Only complete triplets are translated. If the chosen frame leaves one or two bases over at the end, they cannot form a codon, so they are ignored and the tool tells you how many trailing bases were dropped.

What is the Codon to Amino Acid Translator?

Takes a DNA or mRNA sequence, reads it in non-overlapping triplets from a chosen frame, and returns the translated amino acid sequence in one and three letter codes using the standard genetic code, marking stop codons. For molecular biology and bioinformatics. It runs free in your browser on Gera Tools, with nothing uploaded.

Codon to Amino Acid Translator

Name: Codon to Amino Acid Translator
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

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Translating a coding sequence into protein means reading it three bases at a time and looking each triplet up in the genetic code. This tool does exactly that for any DNA or mRNA you paste, in your chosen reading frame, and reports the protein in both one-letter and three-letter codes.

How it works

The sequence is cleaned of spaces, uppercased, and any thymine is converted to uracil so DNA and RNA behave identically. Starting from the chosen frame, the tool walks the sequence in non-overlapping triplets and maps each codon through the standard genetic code table.

AUG maps to methionine, the three stop codons map to an asterisk, and the other sixty codons map to their amino acids. Any one or two bases left over at the end cannot complete a codon and are reported as ignored.

The standard genetic code at a glance

The 64 codons map to 20 amino acids plus stop signals. A few key landmarks:

AUG is the only start codon in the standard code and also codes for methionine (Met, M).
UAA, UAG, UGA are the three stop codons (shown as * in one-letter output).
The genetic code is degenerate: most amino acids are coded by more than one codon. Leucine, for example, has six synonymous codons (UUA, UUG, CUU, CUC, CUA, CUG).
Only methionine (AUG) and tryptophan (UGG) have a single codon each.

This degeneracy is why silent mutations — changes that swap one codon for a synonymous one — often have no effect on the protein sequence.

Worked example

The DNA ATGGCCTTAGGCTAA read in frame +1 splits into ATG GCC TTA GGC TAA, which translates to Met-Ala-Leu-Gly-Stop, or MALG* in one-letter code.

Shifting to frame +2 starts at the second base (TGGCCTTAGGCTAA), producing TGG CCT TAG GCT A — Trp-Pro-Stop-Ala — a completely different, much shorter reading with an early stop codon. This illustrates why frame selection matters so much.

Reading frame identification tips

If you do not know the correct frame, try all three and apply these heuristics:

The correct ORF (open reading frame) usually starts with Met (AUG) and runs for many codons before the first stop.
Incorrect frames typically hit a stop codon within a few triplets.
If you have the protein length from a database record, count which frame produces a matching number of codons before the stop.

Remember this tool translates the strand you paste as written. To translate the complementary strand, reverse complement the sequence first. The standard NCBI table 1 is used here — mitochondrial and a few bacterial codes differ and need a specialised tool.