ZIP Extractor
Extract ZIP files entirely in your browser and list, preview, and download their contents. Automatically detects and fixes garbled filenames from ZIPs created on Windows (Shift_JIS). Files are never sent to a server.
What this browser-based ZIP extractor does
This tool opens a ZIP file entirely inside your browser and lets you list its contents, preview them and download individual entries. It is handy where you cannot install extraction software, or when you want to glance inside an archive on a shared machine. Password-protected ZIPs are supported, both AES-256 and the older ZipCrypto.
A recurring nuisance is garbled file names. The ZIP specification allows entries that carry no information about the character encoding of their names, so an archive created on Windows in a non-Latin locale can open with the names mangled. This tool attempts to detect the encoding automatically and, where that fails, lets you choose one by hand. The contents of the file are never sent to a server.
How to extract a ZIP
- Load the ZIP file Drop the file onto the panel or click to select it. Its contents are not transmitted anywhere.
- Check that the file names look right If the names are mangled, switching the encoding — to Shift_JIS or another legacy set — usually makes them display correctly.
- Enter the password If the archive contains protected entries, a field for the password appears.
- Inspect the contents and pull out what you need Download entries one at a time from the list, or extract them all together. Taking only the files you actually want is perfectly possible.
Tips for getting more out of it
- Garbled filenames usually happen because the ZIP format itself, in many cases, doesn't store which character encoding a filename uses. A ZIP created on Japanese Windows is almost always Shift_JIS, while most others are UTF-8 — so if names look garbled, try switching the encoding dropdown to Shift_JIS.
- Files whose UTF-8 encoding is explicitly flagged inside the ZIP itself never get the ? mark. Only filenames that had to be guessed carry that mark.
- Click a folder row to expand or collapse it. Click a file row to preview text or image files right there.
- In Chrome or Edge, choosing a folder with "Extract All" writes everything out directly while preserving the original folder structure. In other browsers, files are downloaded individually and the folder structure cannot be preserved (the path is instead baked into the filename with underscores).
- Password-protected (encrypted) ZIP files are supported too. Files marked with a lock icon can't be extracted or previewed until you enter the password in the field above. Both the AES-256 method and the legacy ZipCrypto method are supported.
When this is useful
Opening an archive where no extraction software is available
On a shared office machine, or a PC whose settings you cannot change, you can still look inside using nothing but the browser — no waiting for approval to install anything.
Recovering mangled file names
When a ZIP created on Windows opens on a Mac with broken names, specifying the character encoding shows you what the names really are.
Taking a single file out of a large archive
When you want just one item from a sizeable ZIP, you can download it individually rather than expanding the whole thing.
Checking the contents before opening them
You can see at a glance what a ZIP you have received contains, which is a sensible check for anything unexpected.
Terms used with ZIP files
- ZIP
- A format that gathers several files into one and compresses them. Most operating systems support it out of the box.
- Entry
- An individual file or folder held inside a ZIP. Each carries its own name and details of how it was compressed.
- AES-256
- A strong encryption method used in ZIP files. It is regarded as more secure than the older ZipCrypto.
- ZipCrypto
- The legacy encryption method for ZIP. It is very widely compatible but weaker than AES.
- Central directory
- The catalogue of stored files placed at the end of a ZIP. Reading it alone is enough to list the contents.
- Encoding flag
- The marker indicating that a file name is in UTF-8. For entries without it, the encoding of the name has to be guessed.
Frequently Asked Questions
Side Note — Why ZIP Filenames Get Garbled
When the ZIP format was born in 1989, there was no mechanism to record which character encoding a filename used. Each country and operating system simply wrote filenames using its own local encoding (Shift_JIS for Japanese, Windows-1252 for Western European languages, and so on), so garbled text when opening a ZIP on a different system was, in a sense, "working as designed."
To fix this, a mechanism called the "Language encoding flag (EFS)" was added starting around 2007. It uses a single bit in each ZIP entry's flags to explicitly mark "this filename is written in UTF-8." However, older ZIP tools — and some software that still doesn't set this flag — remain in use, so the garbled-filename problem between Windows and Mac still hasn't been fully solved even in the 2020s.
Note that this garbling is not damage to the data itself. The file's actual content (the bytes of the text or image) stays perfectly intact — only the filename, a piece of metadata, is being interpreted with the wrong rule. That's exactly why, once you know the correct encoding, a tool like this one can go back and restore the correct name.