Open GBK files in your browser
The record NCBI, Addgene and every plasmid tool write a DNA sequence in, with its genes and features. Open one right here as its map and sequence, with no SnapGene. Nothing leaves your device.
Or drop it anywhere on this page
What you'll see
Your sequence opens on its map, circular or linear, with its features, primers and the enzymes that cut it once.
- The map • Features as arrows in their colors, primers and unique cutters
- The sequence • Both strands, the features under them and each protein
- Find bases on either strand • IUPAC's codes, or a feature by name
- Export • The map as SVG or PNG, the sequence as GenBank or FASTA
About GBK
GenBank is NCBI's database of every published DNA sequence, and its flat file is the record it hands out: a LOCUS line with the name, the length and whether the molecule is circular, the definition, accession and organism, then the features, then the sequence itself. Addgene, Benchling, SnapGene and ApE save plasmids in it too, so it's how a construct goes from one lab to the next, as .gb, .gbk or .gbff.
Each feature has a type, like CDS, promoter, rep_origin or primer_bind, a location such as complement(join(100..250,300..450)), and qualifiers for its name, its gene, its product and the protein it codes for. ApE and SnapGene add the colors they draw each feature in.
Filepeek reads it in your browser and draws the map, circular or linear, each feature an arrow in its color with its name, its primers, and the enzymes from a list of common ones that cut it once. Sequence runs both strands in rows with the features under them and each coding feature's protein, Features lists them, and a selection gives its place, length and GC. Find looks for bases on either strand in IUPAC's codes, or for a feature by name, and Export saves the map as SVG or PNG and the sequence as FASTA.
GenBank sequence file
.gbk • .genbank • .gbff
Format
- MIME type
- chemical/seq-na-genbank
- Made by
- NCBI, the US National Center for Biotechnology Information
- Released
- 1982
Inside the file
- Header
- LOCUS, DEFINITION, ACCESSION and SOURCE
- Features
- A type, a location and qualifiers
- Sequence
- Numbered rows under ORIGIN
- Written as
- Plain text in fixed columns
Opens in every browser
Filepeek opens GenBank files in Chrome, Edge, Firefox and Safari, a whole bacterial genome included. On their own, browsers download them or show them as text.
- YouChromeOpens through Filepeek
- YouEdgeOpens through Filepeek
- YouFirefoxOpens through Filepeek
- YouSafariOpens through Filepeek
Apps that open GBK
- WindowsSnapGene Viewer, free • UGENE and Benchling
- MacSnapGene Viewer, free • ApE and UGENE
- iPhone and iPadNo app opens it
- AndroidNo app opens it
Questions
How do I open a GenBank file without SnapGene?
Drop it on this page or choose Peek a GBK. The map, the sequence and the features open in your browser, with nothing to install, on a phone too.
Is a .gb file GenBank or a Game Boy game?
Either. Filepeek reads its first line: a GenBank file starts with LOCUS, so it opens as a sequence, and a Game Boy game opens as a ROM.
How do I find a sequence in a plasmid?
Type it in Find. It looks on both strands and reads IUPAC's codes, so N matches any base and R an A or a G, and Enter steps through the matches.
Which enzymes does the map show?
Those from Filepeek's list of common enzymes that cut the sequence exactly once, where a single digest opens a plasmid. Enzymes hides them.
Can I turn a GenBank file into FASTA?
Yes. Choose Export, then Save as FASTA, with every record in the file one after another.