🧬 DNA Reverse Complement & Translate
Reverse-complement, transcribe (DNA→mRNA) and translate any DNA or RNA sequence — exact on sequences of any length, processed entirely on your device.
18 nt · GC 50.0% · DNA · 🔒 stays in your browser
Reverse complement (5′→3′)
TTAGTCGCTGAAGGCCAT
How the dna reverse complement & translate works
Paste a sequence (FASTA headers and spaces are ignored). The reverse complement pairs A↔T, G↔C (A↔U for RNA) and reverses 5′→3′. Transcription copies the coding strand to mRNA (T→U). Translation reads codons in your chosen frame through the standard genetic code, showing the protein until a stop codon. GC content and length are reported alongside.
Your sequence never leaves the browser — this matters for unpublished or proprietary constructs that shouldn’t be pasted into a chatbot or an upload site. The standard genetic code and base-pairing rules are fixed constants, so the output is exact and never goes out of date.
Frequently asked questions
What is a reverse complement?
The reverse complement of a DNA strand is the sequence of its complementary strand read 5′→3′. You complement each base (A↔T, G↔C) and then reverse the order. For ATGC the complement is TACG and the reverse complement is GCAT.
How do I translate DNA to protein?
Read the sequence in codons (groups of three) from your reading frame and map each codon to an amino acid using the standard genetic code. ATG starts as Methionine; TAA, TAG and TGA are stop codons. This tool does it exactly, in any of the three frames.
Is my sequence uploaded anywhere?
No. Every operation runs in your browser using JavaScript — the sequence is never sent to a server. That is deliberate: sequence data is often unpublished or proprietary and should not be pasted into cloud tools.
Does it handle RNA and IUPAC ambiguity codes?
Yes. It detects RNA (U instead of T) and complements IUPAC ambiguity codes (N, R, Y, S, W, K, M, B, D, H, V) correctly.
What is the difference between complement and reverse complement?
The complement pairs each base in place (ATGC → TACG). The reverse complement also reverses the order (ATGC → GCAT), which is what you need to design a primer or find the opposite strand read 5′→3′.
How long a sequence can it handle?
As long as your device’s memory allows — there is no server limit. Unlike a chatbot, the output is byte-exact even for multi-kilobase sequences.
Related biology & lab tools
From the blog
How to Predict Restriction Digest Fragment Sizes
A restriction digest cuts DNA into fragments — and you can predict their sizes from the sequence before you run the gel. Here's how cut positions become fragment sizes, why linear and circular DNA differ, and what the prediction can't tell you.
Reverse Complement of DNA: The Rule, the Steps, and Why Direction Matters
The reverse complement of ATGC is GCAT — complement each base (A↔T, G↔C), then reverse to read 5′→3′. Why it's not the same as the complement, how translation and transcription differ, and why you shouldn't paste sequences into a chatbot.