How is mRNA turned into protein?

Ribosomes read mRNA in 3-nucleotide codons starting at AUG. Each codon specifies one amino acid via the standard genetic code; translation stops at UAA, UAG, or UGA.

How do you transcribe mRNA into protein?

Strictly speaking, mRNA is translated (not transcribed) into protein. Group the mRNA into codons from the start AUG, look up each in the codon table, and chain the amino acids.

What alphabet does this tool accept?

Only the four RNA bases: A (adenine), U (uracil), G (guanine), C (cytosine). For DNA sequences (using T), convert with a DNA-to-mRNA tool first.

Does translation always start at AUG?

Yes — the tool scans for the first AUG and reads from there. Nucleotides before the first AUG (the 5' UTR) are shown but not translated.

What happens at stop codons?

Translation halts at the first UAA, UAG, or UGA. The stop codon itself is not converted to an amino acid; it is labelled STOP in the output.

Can I translate without a start codon?

Yes — toggle "Force full translation" to read every codon from the beginning regardless of AUG. Useful for analysing arbitrary reading frames.

mRNA to Protein Translator

Translate an mRNA sequence (A, U, G, C) to its amino acid chain using the standard genetic code. Detects AUG start and UAA/UAG/UGA stops.

mRNA Sequence Input

Nucleotide Sequence (A, U, G, C)

Spaces and newlines are ignored. Enter only A, U, G, C.

Force full translation (ignore start codon)

Quick samples

Enter an mRNA sequence and click Translate

Codons Read

Amino Acids

—

Stop Codon

Protein Sequence (1-letter)

Codon Table

#	Codon	1-Letter	3-Letter	Amino Acid

Copied!

Summary

Enter any mRNA nucleotide sequence and this tool reads it in triplet codons, looks each one up in the standard genetic code table, and returns the full amino acid sequence. It detects the AUG start codon and stops at UAA, UAG, or UGA. Results include single-letter codes, three-letter abbreviations, and full amino acid names.

How it works

Paste or type your mRNA sequence (A, U, G, C — spaces and line breaks are stripped automatically).
Click Translate to scan from the first AUG start codon and read subsequent triplet codons.
Each codon is matched against the standard genetic code to produce an amino acid.
Translation stops at the first UAA, UAG, or UGA codon (labelled STOP, not converted).
Results show single-letter codes, three-letter abbreviations, and full amino acid names.

Use cases

Verify a predicted protein sequence from a cloned cDNA.
Check open reading frames (ORFs) in a transcribed mRNA sequence.
Teach or learn the standard genetic code and codon table.
Validate the output of a PCR-derived or synthesized mRNA fragment.
Compare codon usage across reading frames using the force-full-translation toggle.

Frequently Asked Questions

Last updated: 2026-09-30 · Reviewed by Nham Vu