Clean DNA, RNA, and protein sequences online. Remove spaces and numbering, check sequence characters, and format single or multi-FASTA records in your browser.
Paste raw sequence text or load a text-based sequence file. Choose the alphabet and cleanup rules, then select plain text, FASTA, or printable dsDNA output.
Accepts up to 1,000,000 cleaned sequence characters, 1,000 records, and 1,000 characters per FASTA header.
No cleanup changes were applied.
Sequence text copied from papers, GenBank-style displays, PDFs, email, or lab documents often contains spaces, line numbers, inconsistent case, and hidden line endings. Conservative cleanup removes known formatting artifacts while leaving unexpected characters visible for review.
Sequence cleanup removes text-formatting artifacts; it does not correct sequencing errors or assess biological quality.
When used as a DNA sequence cleaner with the default settings and FASTA output, this tool removes spaces and sequence numbering while preserving the header and biological sequence, as shown below. The same formatting cleanup also applies to RNA and protein records.
Before:>sample_1
1 ATGC ATGC 8
9 TTAA 12
After:>sample_1
ATGCATGCTTAA
Each FASTA record begins with a single header line starting with >, followed by one or more sequence lines. Line wrapping changes readability but not the biological sequence. Common widths include 60, 70, and 80 characters.
Silently deleting an unexpected character can alter a biological sequence. This tool therefore keeps and reports unsupported characters by default. Removal or replacement with N for nucleic acids or X for proteins requires an explicit selection.
The dsDNA view displays the entered strand 5′ to 3′ and its complementary strand antiparallel from 3′ to 5′. It is a readable presentation format, not a FASTA representation.