How do you convert DNA into mRNA?

Read the DNA template strand 3' to 5' and write each base's RNA complement: A→U, T→A, G→C, C→G. The result, read 5' to 3', is the mRNA transcript. This tool applies those rules automatically.

What base-pairing rules does this tool use?

During transcription the DNA template strand is read 3' to 5' and the mRNA is synthesized 5' to 3'. Base pairs are: A (DNA) → U (mRNA), T (DNA) → A (mRNA), G (DNA) → C (mRNA), C (DNA) → G (mRNA).

What does DNA → RNA → protein mean?

This is the central dogma: DNA is transcribed into mRNA (this tool), then mRNA is translated into a protein at the ribosome via tRNA and the genetic code. To go further, use an mRNA-to-protein translator.

Should I enter the template strand or the coding strand?

Enter the template strand (also called the antisense or non-coding strand). The mRNA produced will match the coding strand sequence, except T is replaced by U.

What characters are accepted?

Only A, T, G, and C (case-insensitive). Spaces, numbers, and other characters are ignored so you can paste FASTA-style sequences or sequences with line numbers.

Can I group the output into codons?

Yes. Toggle the "Group by codons (triplets)" option to display the mRNA output as space-separated triplets, making it easier to read during translation.

Is there a length limit?

The tool handles sequences up to 100,000 bases without issues. For very large sequences the display is truncated to the first 10,000 characters but the full sequence is always copied correctly.

DNA to mRNA Converter

Paste a DNA template strand sequence and instantly get the corresponding mRNA transcript using standard base-pairing rules.

DNA Template Strand

Enter bases A, T, G, C — case-insensitive. Other characters are ignored.

Group by codons (triplets) Uppercase output

Base Pairing Reference

A U Adenine → Uracil

T A Thymine → Adenine

G C Guanine → Cytosine

C G Cytosine → Guanine

mRNA Transcript

Enter a DNA sequence and click Convert

Copied!

Summary

This tool converts a DNA template strand sequence into its mRNA transcript by applying the standard base-pairing rules: A pairs with U, T pairs with A, G pairs with C, and C pairs with G. The conversion runs entirely in your browser — no data is sent to any server. Both single-strand and multi-line input formats are accepted.

How it works

Enter or paste a DNA template strand sequence (A, T, G, C) into the input field.
Non-nucleotide characters are automatically stripped or flagged as errors.
Each DNA base is mapped to its complementary mRNA base: A → U, T → A, G → C, C → G.
The resulting mRNA sequence is displayed with optional codon grouping (triplets).
Use the Copy button to copy the mRNA sequence to your clipboard.

Use cases

Quickly verify transcription base-pairing for biology homework or coursework.
Check mRNA sequences during molecular biology research or lab prep.
Teaching students the central dogma — DNA transcription step.
Generating mRNA sequences from known gene template strands for analysis.
Cross-checking manual transcription work to catch base-pairing errors.
Preparing sequences for downstream codon analysis or protein translation.

Frequently Asked Questions

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