How to open RAR, 7z and ZIP files without installing anything

Someone sends you a .rar with project files, a .7z with photos or a .tar.gz backup, and you are on a work laptop where you cannot install software, a Chromebook, or a phone. This guide shows how to get the files out in the browser, when your device's built-in tools are enough, and what to do when an archive refuses to open.

Check what your device already does

Before reaching for any tool, it helps to know what is built in.

• Windows 11: File Explorer opens ZIP files natively, and recent Windows 11 updates added support for opening RAR, 7z and TAR archives as well. Double-click the archive, or right-click and choose Extract All.
• Windows 10: ZIP only. RAR and 7z need another program.
• Mac: double-clicking a ZIP or a TAR.GZ unpacks it with the built-in Archive Utility. RAR and 7z are not something to count on without an extra app.
• iPhone and iPad: the Files app expands a ZIP when you tap it. Other formats are not supported.
• Android: most file manager apps, including the common Files apps, extract ZIP. Support for anything else varies by phone.

If your archive is a ZIP and you are on a computer, the built-in route is usually all you need. The browser route is for everything else: other formats, devices where you cannot install anything, or archives where you only want one file out of hundreds.

Extract in the browser

1. Open Unzip online and drop the archive. Supported: ZIP, RAR (RAR4 and RAR5), 7z, TAR, TAR.GZ, TGZ, BZ2, XZ, ISO and CAB, up to 1 GB.
2. The full list of files appears with their uncompressed sizes, sorted by folder. Everything is selected by default.
3. Click download next to a single file to save just that file.
4. Or untick what you do not need and download the selection. Several files are packed into one ZIP named after the archive, with the folder structure kept inside.

The archive is read by libarchive, compiled to WebAssembly and running in a background worker in your tab. The file is not uploaded anywhere. That makes it a reasonable way to look inside an attachment before trusting it: you see the list of file names and sizes, and nothing in the archive is run.

Password-protected archives

When an archive contains encrypted files, a password field appears. Enter the password and download as usual; it is checked on the first file you extract, and a wrong password gives a clear message rather than broken files.

This works for password-protected ZIP files. Encrypted RAR and 7z archives cannot currently be decrypted in the browser; the tool recognises them and tells you so straight away instead of asking for a password. For those you need a desktop archiver on a computer where you can install one.

Common password problems:

• Passwords are case-sensitive, and caps lock is the most frequent culprit.
• Copying a password from an email or chat often brings a trailing space or line break with it. Type it by hand if a correct password is rejected.
• There is no recovery for a forgotten password. Ask the sender.

Working on a phone

Phones are where the browser route helps most, because the built-in support stops at ZIP.

• iPhone: in Mail or a messenger, save the attachment to Files first. Open the tool in Safari, tap the drop area and pick the archive from Files. Extracted files land in Downloads, from where you can move them, or save photos to your library through the share sheet.
• Android: open the tool in Chrome and pick the archive from Downloads. Extracted files are saved to Downloads.
• Memory: extraction happens in the device's memory. Archives of a few hundred megabytes are fine on most recent phones; a large archive with big files may fail. Download a few files at a time instead of all of them.

Archives from other people often need a second step

What comes out of an archive is rarely the right size for its next use.

• Photos from a shoot or a camera dump are usually full resolution. For email, a website or a form, run them through Compress JPG at 75 to 85%, which typically cuts the size by more than half.
• Scanned PDFs can be several megabytes per page. Compress PDF makes them small enough to forward, at the cost of turning pages into images.
• Sending the files on in a format everyone can open: pack them into a ZIP with Create ZIP. A ZIP opens on every computer and phone without extra software, which is not true of RAR or 7z.

The formats in two lines each

• ZIP: the universal format, opened natively everywhere. Moderate compression; encryption is either the weak legacy method or AES.
• RAR: a proprietary format common for large downloads and multi-part sets. Creating RAR files requires its own software; reading is widely supported.
• 7z: the 7-Zip format. Usually compresses better than ZIP, especially on text and code, and is popular for software and game mods.
• TAR.GZ, TAR.BZ2, TAR.XZ: the Unix family. TAR bundles files into one, the second extension says how the bundle was compressed. Typical for source code and server backups.
• ISO: an image of a disc. You can pull individual files out without mounting or burning it.
• CAB: Microsoft's format, found inside installers and driver packages.

Troubleshooting

• "Could not open this archive." The file is usually incomplete, most often an interrupted download or an attachment that was cut off. Compare its size with what the sender expected and download it again.
• The archive has parts. Files named .part1.rar, .part2.rar, or .z01, .z02, or .7z.001 are pieces of one archive. Each part alone cannot be opened, here or anywhere. You need all parts in the same folder and a desktop archiver to join them.
• A double extension like .tar.gz. Drop it as it is; the tool handles both layers and shows the files inside.
• File names are garbled. Old ZIP files made on Windows in non-Latin languages sometimes store names in a legacy encoding. The contents are intact; rename the files after saving.
• Extraction stops on a large archive. The browser ran out of memory. Select fewer files per download, or use a computer instead of a phone.
• The archive contains .exe, .scr, .js or .bat files you did not expect. Treat it as suspicious, especially from an unknown sender. Do not extract and run them; delete the archive.
• A file is missing after extraction. Check that it was ticked. Empty folders are not included in the downloaded ZIP.

Checklist

1. Try the built-in extractor if the archive is a ZIP and you are on a computer.
2. Use the browser for RAR, 7z, TAR and ISO, or on phones and locked-down machines.
3. Look at the file list before extracting anything from an unknown sender.
4. Download only the files you need.
5. For encrypted RAR or 7z, use a desktop archiver.
6. Join multi-part archives on a computer first.
7. Compress or re-pack extracted files before sending them on.