Locate DNA sequences that match a regular-expression pattern on both the direct and reverse-complement strands.
Paste one or more raw or FASTA-formatted sequences (limit 500,000,000 characters). White space and digits are removed before searching.
Enter a JavaScript-style regular expression without surrounding slashes. Example: ctt[ca].
Paste one or more DNA sequences in FASTA format or as raw text. White space and digits are automatically removed before searching (limit 500 million characters).
Enter a JavaScript regular expression pattern without surrounding slashes. Use character classes like [ca] to match alternatives, quantifiers like {2,5} for repeats, or IUPAC codes for degeneracy.
The tool automatically searches both the direct strand and the reverse complement, reporting matches with their positions and strand information.
Each match is numbered and shows start/end positions (1-based), the matching sequence, and whether it was found on the direct or reverse strand.
Use character classes (e.g. `[AG]`) or explicit IUPAC letters to capture ambiguity in the DNA motif you are targeting.
Matches are reported on both the direct strand and the reverse-complement, mirroring the original SMS behaviour.
Remember that JavaScript regex syntax is used, so anchors like `^` and `$`, or quantifiers like {2,5}, behave as expected.