Archive format
What is a .zip file?
ZIP is the most common archive format. It packs several files and folders into one and compresses them without loss.
Windows, macOS, iOS and Android open it without extra software. Photos and video already compressed barely shrink inside a ZIP.
fileclay unpacks and creates ZIP
ZIP vs TAR vs GZ
| ZIP | TAR | GZ | |
|---|---|---|---|
| Several files | Yes | Yes | No |
| Compresses | Yes | No | Yes |
| Built into Windows | Yes | Windows 11 | Windows 11 |
| Best for | Sharing folders | Packing on Linux | Compressing one file or a TAR |
When to use ZIP
Good for
- Sending several files at once
- Backing up a folder
- Reducing the size of documents and text
Not a good fit
- Shrinking photos or video: they are already compressed
- Strong protection without AES encryption
- Keeping Linux file permissions: TAR does it better
How to open .zip files
| Platform | App | Notes |
|---|---|---|
| Windows | File Explorer | Built in |
| macOS | Finder | Built in |
| iPhone, iPad | Files | Built in |
| Android | Files by Google | Built in |
| Any system | 7-Zip, WinRAR | More options |
Convert ZIP files
Drop a .zip into the converter and it’s unpacked. Results can also be downloaded as one archive.
Conversions run in your browser. Files aren’t uploaded.
How to identify a .zip file
A ZIP starts with “PK”, the initials of Phil Katz. DOCX, XLSX, ODT and EPUB start the same way, because they are ZIP files inside.
It’s read here, in your browser. Only the first bytes.
Your file
What comes after
Questions about ZIP
Does a ZIP reduce file size?
It does for text and documents. Photos, video and MP3 barely change.
Does zipping lose quality?
No. The files come out identical.
Is a password-protected ZIP safe?
With AES encryption, yes. The older ZipCrypto method is weak.
Can ZIP files be larger than 4 GB?
Yes, with the Zip64 extension.