File Operations

ZIP Creator

Compress multiple files or folders into a ZIP archive entirely in your browser, then download it. Dropping a folder preserves its original folder structure inside the ZIP. Files are never sent to a server.

Tips for Creating a ZIP

  • Drop a whole folder and it will be stored in the ZIP with its original folder structure preserved. If you select individual files instead, the resulting ZIP will be flat, with no folder structure.
  • Unchecking "Compress" switches to the STORED (no compression) method, which runs much faster. When bundling files that are already compressed — images, video, audio, ZIP files, and the like — the size barely changes either way, so skipping compression is faster with almost no downside.
  • If you add multiple files with the same name, they are automatically distinguished with a number, like "filename (1).ext". The original contents are never overwritten or lost.
  • Bundling a huge number of files, or very large files, can take a while since everything is processed in your browser's memory — and it may even fail depending on your device. For anything from a few hundred megabytes up to several gigabytes, we recommend splitting the job into a few smaller ZIPs.

Frequently Asked Questions

No. Compression happens entirely inside your browser, and the file's contents are never sent to a server.

Not in the current version. It's on the roadmap as a possible future feature.

Yes. If you drop a folder with no contents, the folder itself is still kept as an entry in the ZIP.

Use the "ZIP Extractor" tool in the same File Operations category. It also automatically fixes garbled filenames between Windows and Mac.
ツールくん

Side Note — What Can (and Can't) Be Compressed

ZIP's DEFLATE compression excels at data where the same pattern repeats, like text files or bitmap images. Files that are already compressed — JPEG, PNG, MP4, MP3, and so on — have almost no repeating patterns left, so putting them in a ZIP barely changes their size (it can even grow slightly).

This property, turned on its head, is exactly how a "zip bomb" works. A file that repeats a single character (say, the digit 0) over and over compresses at an almost unbelievable ratio — in theory, a ZIP just a few kilobytes in size could expand to several terabytes once extracted. That's one reason it isn't a good idea to blindly extract every file inside a ZIP you don't trust.

Incidentally, files ending in ".zip" aren't the only ones that are actually ZIP files under the hood. Microsoft Office's .docx and .xlsx, Java's .jar, and Android's .apk are all built on a ZIP container holding multiple files internally. ZIP is used far more widely than you might expect, as a kind of universal "box for bundling several files into one."

More tools in this category