Open a .bz2 online

Q: How do I open a .bz2 file online?

Open the page and drop your `.bz2` onto it. ZipTool decompresses the file inside it in your browser — no command line, no install, no upload. The original file opens immediately (text, code, image, PDF, audio, or video depending on what was compressed), and you can read or download it.

Q: What is the difference between .bz2 and .tar.bz2?

A `.bz2` is a single file compressed with bzip2 — it decompresses to one file. A `.tar.bz2` is a tar bundle of many files that was then compressed with bzip2 — it opens as a folder tree. If you expected many files from a `.bz2`, you likely have a `.tar.bz2`. ZipTool opens both: a `.bz2` as one file (this page), a `.tar.bz2` as a tree ([/tar-bz2](/tar-bz2)).

Q: Can it open .gz, .zst, or .xz files too?

Yes — a lone `.gz` opens on [open a .gz online](/gz), a `.zst` on [open a .zst online](/zst), and an `.xz` on [open an .xz file online](/xz); their tarball forms have their own pages ([.tar.gz](/tar-gz), [.tar.zst](/tar-zst), [.tar.xz](/tar-xz)). LZ4 is not supported; use the command line or a desktop tool for that.

Decompress (bunzip2) a .bz2 file in your browser — no command line, no upload.

Load from cloud

Drop your .bz2 anywhere on this page

Decompressed entirely in your browser — your file is never uploaded.

A .bz2 is a single file compressed with bzip2 — dump.sql.bz2, data.xml.bz2, a log archive, an old backup. It is not a multi-file container: bzip2 is a stream compressor, so a lone .bz2 holds exactly one file, and "opening" it means undoing the bzip2 compression (the bunzip2 operation) to get that one file back. ZipTool does it in your browser with a bzip2 decoder bundled into the page: you drop the .bz2 on it and the decompressed file opens immediately, with nothing uploaded and nothing installed.

You open the page, drop the .bz2 onto it (or paste a direct URL), and the original file renders locally — text and code in a syntax-highlighting editor, images, PDFs, audio, and video depending on what was inside. The decode runs entirely in your tab; the network is used only to load the page.

.bz2 versus .tar.bz2 — they are not the same

The two extensions are constantly confused, and the difference matters. A lone `.bz2` is one compressed file — report.csv.bz2 decompresses to one report.csv. A `.tar.bz2` (or .tbz2, .tbz) is a tar bundle of many files that was then compressed with bzip2 — it opens as a whole folder tree. If you expected many files from a .bz2 and got one, you almost certainly have a mistyped .tar.bz2.

ZipTool handles both honestly: a .bz2 opens as the single file inside it, and a .tar.bz2 opens as a folder tree — see open a .tar.bz2 online. The sibling compressors work the same way: open a .gz online, open a .zst online, and open an .xz file online for single compressed files.

How to open a .bz2 in your browser

No bunzip2, no terminal, no install. The page decodes the stream locally.

Go to ZipTool and drag the .bz2 onto the page (or use the file picker, or paste a URL).
The single file inside is decompressed and opened — text and code show in the editor, images and PDFs render, audio and video play.
Download the decompressed file to keep it, or search and read it in place.
Nothing is uploaded — confirm it by opening a .bz2 and turning off your internet; viewing keeps working.

What makes bzip2 different — the Burrows–Wheeler trick

bzip2 (Julian Seward, 1996) does not compress byte-by-byte the way gzip's Deflate does. It first applies the Burrows–Wheeler transform (BWT) — a reversible shuffle of the whole block that groups similar contexts together — then move-to-front coding and Huffman coding on the result. Because the transform reorders data rather than sliding a window over it, bzip2 reaches ratios that regularly beat gzip and often land between gzip and xz, at the cost of being slower in both directions and working on fixed blocks (100 kB to 900 kB, set by the level digit 1–9 that appears right in the header after the BZh magic).

That block structure had a famous side effect: a .bz2 stream can be decompressed in parallel block-by-block, which made it the distribution format of choice for enormous single files — Wikipedia's database dumps shipped as .bz2 for years. You still meet .bz2 on older Linux packages, Debian-era source bundles, and long-lived data dumps; modern pipelines mostly moved to xz (smaller) or zstd (much faster), but the files live on.

Honest limits

A browser-based bzip2 decompressor is simple and reliable, with a couple of boundaries.

A .bz2 is one file, not a folder. bzip2 compresses a single stream; it is not a packager. If you need many files out, you have a .tar.bz2, not a .bz2 — see open a .tar.bz2 online.
bzip2 streams carry no filename. gzip has an optional FNAME field; bzip2 has no equivalent, so the decompressed file takes the container's name minus the .bz2 — data.json.bz2 opens as data.json.
Decompression is one pass over the whole stream. bzip2's JavaScript decoder works block-by-block but cannot report a byte-precise progress fraction, so large files show a plain spinner rather than a percentage — the decode still runs entirely in your tab.
Other compressors have their own pages. gzip (/gz), zstd (/zst), and xz (/xz) are supported; LZ4 is not. Use the command line or a desktop tool for LZ4.
bz2 is a source, never a target. ZipTool's converter accepts .bz2 and .tar.bz2 archives as input and repacks them as ZIP, TAR, or TAR.GZ — it never writes .bz2 output.

Frequently asked questions

How do I open a .bz2 file online?

Open the page and drop your .bz2 onto it. ZipTool decompresses the file inside it in your browser — no command line, no install, no upload. The original file opens immediately (text, code, image, PDF, audio, or video depending on what was compressed), and you can read or download it.

What is the difference between .bz2 and .tar.bz2?

A .bz2 is a single file compressed with bzip2 — it decompresses to one file. A .tar.bz2 is a tar bundle of many files that was then compressed with bzip2 — it opens as a folder tree. If you expected many files from a .bz2, you likely have a .tar.bz2. ZipTool opens both: a .bz2 as one file (this page), a .tar.bz2 as a tree (/tar-bz2).

Is bzip2 still worth using?

Mostly for compatibility, not for new archives. bzip2's ratios beat gzip but trail xz, and zstd decompresses several times faster at similar sizes — which is why modern distributions moved on. But .bz2 files remain common in older backups, Debian-era sources, and big public dumps (Wikipedia shipped them for years), so a browser-side bunzip2 is still regularly useful.

Do you upload my .bz2 file?

No. The file is decompressed entirely in your browser; your contents are never sent to a server, never stored, and never handed to a third party. Confirm it in DevTools — the Network tab shows no upload — and by disconnecting from the internet after the page loads: viewing keeps working.

Can it open .gz, .zst, or .xz files too?

Yes — a lone .gz opens on open a .gz online, a .zst on open a .zst online, and an .xz on open an .xz file online; their tarball forms have their own pages (.tar.gz, .tar.zst, .tar.xz). LZ4 is not supported; use the command line or a desktop tool for that.