Open a sequencing file in the browser

Opens as an editable construct (circular or linear map, sequence view, feature table) with every annotation the file carried. Feature-only files (GFF3 without sequence, GTF, BED) open on an unknown-base backbone spanning the features, so the annotations are still editable and exportable.

• BED.bedREAD + WRITE · Export panel
• EMBL.embl.embREAD + WRITE · Export panel
• FASTA.fasta.fa.fna.ffn.faa.fas.fsaREAD + WRITE · Export panel
• FASTQ.fastq.fqREAD ONLY
• GenBank.gb.gbk.genbank.apeREAD + WRITE · Export panel
• Gene Construction Kit.gckREAD ONLY
• Geneious.geneiousREAD ONLY
• GenPept.gp.genpepREAD ONLY
• GFF3.gff.gff3READ + WRITE · Export panel
• GTF.gtf.gff2READ + WRITE · Export panel
• JBEI / raw sequence.seqREAD ONLY
• JSON / OpenCloning.jsonREAD + WRITE · Export panel
• RDF (SBOL construction record).ttl.turtle.nt.ntriples.nq.nquads.trig.jsonldREAD ONLY
• SBOL.sbol.rdfREAD ONLY
• SeqTrace project.strREAD ONLY
• Serial Cloner.xdna.xprtREAD + WRITE · Export panel
• SnapGene.dna.prot.rnaREAD + WRITE · Export panel
• Swiss-Prot / UniProt.dat.sp.swissREAD ONLY
• UniProt XML.uniprotxmlREAD ONLY
• XML (SBOL/JBEI).xmlREAD ONLY

Opens as the chromatogram editor: the four traces, the per-base quality, editable base calls and trim bounds, and a comparison against a reference when you point it at one.

• AB1 trace.ab1.abiREAD ONLY
• SCF trace.scfREAD ONLY
• ZTR trace.ztrREAD ONLY

Opens as the alignment viewer, with per-column conservation and the ability to score the alignment or infer a tree from it.

• ACE assembly.aceREAD ONLY
• Aligned FASTA.afa.a2m.a3mREAD + WRITE · Export panel
• CLUSTAL.aln.clustal.clwREAD + WRITE · Export panel
• GCG MSF.msf.pileupREAD ONLY
• PHYLIP.phy.phylip.phREAD ONLY
• Stockholm.sto.stk.stockholm.pfamREAD ONLY
• Vector NTI AlignX.aprREAD ONLY

Opens in the phylogenetics tool, so a tree someone else inferred lands in the same viewer, re-rooting and comparisons as one built here.

• Guide tree.dndREAD ONLY
• Newick.nwk.newick.tree.treREAD + WRITE · Phylogenetics tool
• NeXML.nexmlREAD + WRITE · Phylogenetics tool
• NEXUS tree.nex.nexusREAD + WRITE · Phylogenetics tool
• PhyloXML.phyloxmlREAD + WRITE · Phylogenetics tool

Opens as a pileup viewer. A BAM is read through its index by locus rather than ingested whole, so a file far larger than memory is still navigable; SAM is read whole, because no index format exists for it.

• BAM.bamREAD ONLY
• SAM.samREAD + WRITE · Export panel

Opens as a variant table with typed INFO and FORMAT fields, per-sample genotypes, allele classification and the summary sections. A bgzipped VCF paired with its .tbi or .csi is read by region rather than ingested.

• BCF.bcfREAD + WRITE · Export panel
• VCF.vcfREAD + WRITE · Export panel

Opens as a sortable, filterable table: results files, primer lists, sample sheets.

• CSV.csvREAD + WRITE · Export panel
• Excel.xlsx.xlsmREAD ONLY
• Excel (legacy).xlsREAD ONLY
• TSV.tsv.tabREAD + WRITE · Export panel

Opens as a table in the same viewer, read column-wise in the browser, so a Parquet file needs no Python to look at.

• Parquet.parquet.pq.parqREAD ONLY

Opens as a PDF reader: the pages themselves, page-by-page navigation, zoom and rotation, drawn in the browser. A paper, a protocol or a supplementary document can sit in the project beside the data it describes rather than in a separate folder.

• PDF.pdfREAD ONLY

Opens as a tensor viewer: shape, dtype and the values themselves, with a slice picker for anything past two dimensions. Both the single-array .npy and the .npz archive are read, stored or compressed, so an array saved out of a Python analysis can be looked at without starting Python.

• NumPy archive.npzREAD ONLY
• NumPy array.npyREAD ONLY

Opens as a 3D structure viewer: the fold itself, drawn as a cartoon, sticks, spheres or lines and colored by chain, by the file’s own secondary-structure annotation, by element or by temperature factor. Beside it the chains and their sequences, the ligands and ordered solvent, the disulfides, the modified residues the file declares, the unit cell and the experiment the coordinates came from. Both serialisations of the archive are read (the fixed-column PDB flat file and PDBx/mmCIF) and an NMR ensemble keeps every conformer it was deposited with rather than being averaged into one.

• CIF structure.cif.mmcifREAD ONLY
• NCBI MMDB structure.prtREAD ONLY
• PDB structure.pdb.entREAD ONLY

Stored verbatim and kept viewable: protocols, reports, exported maps.

• AED region list.aedREAD ONLY
• GMT gene sets.gmtREAD ONLY
• HMMER profile.hmmREAD ONLY
• Markdown.md.markdownREAD + WRITE · Notebook
• SVG.svgREAD + WRITE · Map image and tree image
• Text.txt.textREAD + WRITE · Export panel

CRAM (.cram)

No reader. A .crai index is recognized but can never pair with an alignment, so a CRAM cannot be opened even alongside its index.

BCF (.bcf)

The binary encoding of VCF. No JavaScript or TypeScript reader for it exists; plain and bgzipped VCF are read in full. Convert with `bcftools view -Ov`.

Compressed archives (.gz, .zst) other than a bgzipped VCF

Routing is by extension and compressed files are not unwrapped before dispatch, so a gzipped GenBank is not recognized as GenBank. Decompress it first.

A file with the wrong extension

The format is decided by extension alone, with no inspection of the contents, so a GenBank file saved as .txt opens as text. Rename it.

How do I open a .dna file without SnapGene?

Open it here. SnapGene’s .dna files (and .prot and .rna) are parsed directly into an editable map with their features, primers and notes intact, and can be exported back out as GenBank, FASTA or several other formats.

Can I view an .ab1 file online?

Yes. An .ab1, .abi, .scf or .ztr trace opens as a full chromatogram editor (the four dye traces, per-base quality, editable base calls, adjustable trim bounds and mixed-peak detection) rather than as a static picture of the trace.

Is my file uploaded anywhere?

No. Parsing happens in the browser and projects are saved on the machine you are using. There is no server round trip for a file, which is also why a sequence that is not yet published is safe to open here.

How large a file can it take?

Indexed formats are read by region rather than ingested, so a BAM with its .bai or .csi, and a bgzipped VCF with its .tbi, can be far larger than memory. Formats without an index are read whole and are bounded by what the browser tab can hold.

Can it convert between formats?

Yes. 29 of the 84 formats can be written as well as read, and each one below says which surface writes it: GenBank to FASTA, GFF3 to GenBank, SnapGene to GenBank, GTF to BED and so on. The converter page does it in one step, without opening a project.

Why was my file rejected?

Almost always the extension. The format is decided from the extension alone, with no inspection of the contents, so a renamed or compressed file is not recognized as what it holds: decompress it, or restore the right extension, and it will open.