BYTETOOLS

DNA Codon Translator

Translate a DNA or mRNA sequence into protein across three or six reading frames, with start and stop codons marked and the longest ORF listed.

318
Bases
3
Frames translated
3
Complete ORFs found
105 aa
Longest ORF

Protein for every reading frame

Forward frame 1106 residues · 2 AUG starts · 1 stop

MVHLTPEEKSAVTALWGKVNVDEVGGEALGRLLVVYPWTQRFFESFGDLSTPDAVMGNPKVKAHGKKVLGAFSDGLAHLDNLKGTFATLSELHCDKLHVDPENFR*

Forward frame 2105 residues · 4 AUG starts · 4 stops

WCT*LLRRSLPLLPCGAR*TWMKLVVRPWAGCWWSTLGPRGSLSPLGICPLLMLLWATLR*RLMARKCSVPLVMAWLTWTTSRAPLPH*VSCTVTSCTWILRTSG

Forward frame 3105 residues · 0 AUG starts · 11 stops

GAPDS*GEVCRYCPVGQGERG*SWW*GPGQAAGGLPLDPEVL*VLWGSVHS*CCYGQP*GEGSWQESARCL**WPGSPGQPQGHLCHTE*AAL*QAARGS*ELQV

Open reading frames (ATG to stop)

Strand / frameStartEndCodonsProtein
Forward 11318105MVHLTPEEKSAVTALWGKVNVDEVGGEALGRLLVVYPWTQ…
Forward 26518439MKLVVRPWAGCWWSTLGPRGSLSPLGICPLLMLLWATLR
Forward 219126825MARKCSVPLVMAWLTWTTSRAPLPH

Positions are 1-based and counted along the strand searched, so a reverse-strand ORF is numbered from the start of the reverse complement rather than the sequence you pasted.

Codon by codon — Forward frame 1

ATGMGTGVCACHCTGLACTTCCTPGAGEGAGEAAGKTCTSGCCAGTTVACTTGCCACTGLTGGWGGCGAAGKGTGVAACNGTGVGATDGAAEGTTVGGTGGGTGGAGEGCCACTGLGGCGAGGRCTGLCTGLGTGVGTCVTACYCCTPTGGWACCTCAGQAGGRTTCFTTTFGAGETCCSTTTFGGGGGATDCTGLTCCSACTTCCTPGATDGCTAGTTVATGMGGCGAACNCCTPAAGKGTGVAAGKGCTACATHGGCGAAGKAAAKGTGVCTCLGGTGGCCATTTFAGTSGATDGGCGCTGLGCTACACHCTGLGACDAACNCTCLAAGKGGCGACCTTTTFGCCAACATCTGLAGTSGAGECTGLCACHTGTCGACDAAGKCTGLCACHGTGVGATDCCTPGAGEAACNTTCFAGGRTAG*

Green marks an AUG/ATG methionine, which is where translation starts; red marks UAA, UAG or UGA, the three stop codons that end it.

Translation uses NCBI table 1, the standard genetic code shared by nuclear genes in almost every organism. Vertebrate mitochondria, ciliates, some yeasts and several bacteria reassign a few codons — most famously UGA, which codes for tryptophan rather than a stop in human mitochondria — so results for organellar or unusual sequences need the matching alternative table instead.

What is the DNA Codon Translator?

A codon translator reads a nucleotide sequence three bases at a time and converts each codon into an amino acid using the genetic code. AUG codes for methionine and starts translation; UAA, UAG and UGA are stop codons that end it.

  • Complete standard genetic code, all 64 codons
  • Three forward frames or six across both strands
  • Open reading frame table sorted longest first, with positions
  • Codon-by-codon view with starts and stops colour-coded
  • One-letter and three-letter notation, plus a FASTA download
  • FASTA headers, whitespace and ambiguity codes handled automatically

How to use the DNA Codon Translator

  1. 1

    Paste a DNA or mRNA sequence, with or without a FASTA header.

  2. 2

    Choose three forward reading frames or all six across both strands.

  3. 3

    Switch between one-letter and three-letter amino acid notation.

  4. 4

    Read the protein for every frame, then check the ORF table for the longest coding stretch.

  5. 5

    Pick a frame in the dropdown to see it broken out codon by codon, or download all frames as FASTA.

About the DNA Codon Translator

The ByteTools DNA Codon Translator turns a pasted nucleotide sequence into protein using the standard genetic code, all 64 codons of it. Paste DNA or mRNA — U is read as T automatically — and the tool translates all three forward reading frames, or all six if you want the reverse complement searched as well, showing residue counts, start codons and stop codons for each.

Open reading frames are listed separately: every ATG-to-stop stretch is found, sorted longest first, with its strand, frame, position and protein. A codon-by-codon panel for whichever frame you select colours methionine green and stop codons red, so it is easy to see where a real coding sequence begins and ends.

FASTA headers, line numbers, spaces and punctuation are stripped for you, and IUPAC ambiguity codes are kept as N so any codon containing one becomes X rather than a guess. Every step happens in your browser — sequences are never uploaded — which makes the tool safe for unpublished data and usable offline.

Frequently asked questions

How do you translate DNA into protein?

Read the sequence three bases at a time from a chosen starting point and look each triplet up in the genetic code. ATG gives methionine, GTG gives valine, and so on until you reach TAA, TAG or TGA, which stop translation.

What is a reading frame and why are there six?

A reading frame is where you start counting codons. Beginning at the first, second or third base gives three different frames on one strand, and the reverse complement gives three more — six in total for a double-stranded sequence of unknown orientation.

What is an open reading frame?

It is a stretch that runs from a start codon to an in-frame stop codon with no stop in between, which is what a protein-coding region looks like. Long ORFs are strong candidates for real genes; short ones turn up by chance in any sequence.

Can I paste RNA instead of DNA?

Yes. Uracil is read as thymine, so an mRNA sequence translates exactly as its DNA equivalent would. The tool tells you when it has detected RNA so there is no ambiguity about what it did.

Does this work for mitochondrial or bacterial sequences?

Not exactly. This tool uses the standard genetic code, and vertebrate mitochondria, some yeasts, ciliates and certain bacteria reassign a few codons — UGA codes for tryptophan rather than stop in human mitochondria, for instance. Those sequences need the matching alternative table.

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