Transcribe DNA to mRNA, build the reverse complement, translate codons to protein — standard genetic code, browser-only
- Runs locally
- Category Format Converter
- Best for Turning pasted content or local files into a handoff-friendly format.
Coding strand: the sequence you typed is the sense strand, so transcription is just T→U. Template strand: your sequence is the antisense template, so mRNA is its complement read 5′→3′.
What this tool does
Paste a DNA sequence and get its mRNA transcript, complementary strand and translated protein in one pass. Transcription follows the coding strand by default, so it simply swaps thymine for uracil (T becomes U); flip to template strand and the tool reads the antisense strand and returns the complement built 5′ to 3′ instead. The reverse complement gives you the other DNA strand, also reported 5′ to 3′, which is what you copy when you design a primer or read the opposite strand off a gel. Translation walks the mRNA codon by codon against the standard genetic code, emitting one-letter or three-letter amino acids and stopping at the first stop codon (UAA, UAG or UGA), shown as an asterisk. Spaces, line breaks and case are ignored, so FASTA blocks and hand-typed triplets clean up the same way. Everything runs as plain JavaScript in your tab, with one-click copy on every result and a share link that reopens the exact sequence. No upload, no account, no sequence ever leaves the page.
Tool details
- Input
- Text
- The page exposes text boxes, numeric controls, file pickers, or structured inputs depending on the tool.
- Output
- Live result + Copy
- The result area focuses on usable output, with copy, download, or preview actions when supported.
- Privacy
- Browser-side processing
- The main tool logic does not call an external API, so inputs normally stay in the current tab.
- Save / share
- Shareable URL state
- Key settings are encoded in the URL so another person can reopen the same setup.
- Performance budget
- Initial JS <= 10 KB
- No WASM budget is declared, keeping the tool quick to open on mobile.
- Best fit
- Format Converter · Student
- Category and role tags drive related tools, internal links, and quick fit checks.
How to use
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1. Input
Paste or drop your content into the tool panel.
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2. Process
Click the button. All processing is local in your browser.
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3. Copy / Download
Copy the result or download to disk in one click.
How DNA to RNA Converter fits into your work
Use it when the main problem is getting content from one practical format into another.
Conversion jobs
- Turning pasted content or local files into a handoff-friendly format.
- Previewing a conversion before you use it in a larger workflow.
- Cleaning small format mismatches without opening a full editor.
Conversion checks
- Try a small sample first when the source format is messy.
- Check character encoding, separators, and line endings after conversion.
- Keep the source until the converted output has been reviewed.
Good next steps
These links move the current task into a more complete workflow.
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- 3 Base64 Encoder & Decoder Encode or decode Base64 — text, files, and Data URLs. Runs entirely in your browser. Open
Real-world use cases
Check a transcription answer for a molecular biology class
You are given a coding-strand DNA sequence on a problem set and asked for the mRNA and the protein it makes. Paste ATG TTT TAA, read AUGUUUUAA as the transcript, and see the protein resolve to Met-Phe-Stop. Switch to one-letter codes (MF*) to match the answer key format, and you have checked your work in seconds instead of hand-walking the codon table.
Design a reverse primer from a target sequence
A reverse primer binds the opposite strand, so you need the reverse complement of your forward target. Paste the sense sequence, copy the reverse-complement output (written 5′ to 3′, ready to order), and you skip the error-prone step of flipping and complementing 20 bases by hand on scratch paper.
Translate a candidate open reading frame
You spotted an ATG in a sequence and want to know what protein the frame encodes. Paste from the start codon, read the one-letter chain, and watch translation halt at the first UAA, UAG or UGA so you can see exactly where the reading frame closes and how long the peptide is.
Confirm template-strand transcription on a homework strand
Some textbooks give the template (antisense) strand and ask for the mRNA. Switch the tool to template mode, paste the strand, and it reads 3′ to 5′ to return the complement — so TAC correctly becomes the mRNA GUA rather than a naive T-to-U swap that would give the wrong answer.
Common pitfalls
Transcribing the template strand as if it were the coding strand. If you only swap T to U on the antisense strand you get the complement of the real mRNA. Tell the tool which strand you pasted so it applies T-to-U or complement correctly.
Forgetting the reading frame when translating. The genetic code is read in fixed triplets from the start, so an extra base at the front shifts every codon. AUGUUU reads MF, but a stray leading base would read it as something else entirely.
Reading past the stop codon. Translation ends at the first UAA, UAG or UGA. Bases after the stop are not part of the protein, so a sequence that looks long can encode a short peptide.
Privacy
Transcription, the reverse complement and translation are all plain JavaScript that runs inside your browser tab. No sequence is sent to a server, and nothing you paste is logged. The one exception is the share link, which encodes your sequence in the URL query string — a link pasted into chat will sit in that service's access logs. For unpublished or sensitive sequences, use the copy buttons rather than sharing the URL.
FAQ
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