Sequence Format Converter — FASTA ⇄ GenBank ⇄ TSV
Convert between FASTA, GenBank and tab-separated formats, and extract CDS or protein sequences.
🔒 Local processing — pasted sequences are not uploaded
Convert a sequence from one file format to another without leaving the browser. Paste FASTA or a GenBank flat file — the input format is auto-detected — then pick an output: FASTA sequence, FASTA of the CDS features (as nucleotides or translated protein), a minimal GenBank record, or a tab-separated name/length/sequence table. It is a fast, no-signup way to reformat records copied from NCBI, a paper, or a plasmid editor before feeding them into another tool.
How to use the Format Converter tool
- 1Paste a FASTA or GenBank record (or load the example); the input format is auto-detected.
- 2Choose the output format — FASTA, FASTA of CDS features (nucleotide or protein), minimal GenBank, or tab-separated.
- 3Copy the converted output or download it as a file.
Frequently asked questions
- Which formats can it convert between?
- It reads FASTA and GenBank flat files and writes FASTA (whole sequence), FASTA of each CDS feature as nucleotides or translated protein, a minimal valid GenBank record, or a tab-separated name/length/sequence table.
- How does it extract CDS or protein sequences?
- For GenBank input it reads the FEATURES table, slices each CDS by its location (handling complement(...) and join(...) spans), and either outputs the nucleotide sequence or translates it with the standard genetic code. CDS/protein extraction needs GenBank input, since plain FASTA carries no feature annotations.
- Is my sequence uploaded?
- No. The conversion runs locally in your browser, so your sequence is never uploaded to SeqBench.