What this tool does
The All-file ZIP Compressor packages any set of files — or an entire folder — into one archive that is smaller than the sum of its parts. Unlike the image and PDF tools, this is a general-purpose archive: it accepts documents, spreadsheets, code, images, audio, video, and any other file type. Original filenames and folder structure are preserved.
Compression is performed by the open-source JSZip library, running inside your browser. Files are never uploaded.
How to create a ZIP
- Click Add files to pick individual files, or Add folder to include an entire folder tree.
- Optionally change the compression level: Fast is quickest; Balanced is the usual choice; Maximum is slowest but produces the smallest archive.
- Press Create compressed ZIP — the archive is built in memory and offered as a download.
Lossless vs lossy compression
ZIP is a lossless format: it removes redundancy from the bytes without discarding any information. A Word document, an Excel file or a folder of source code compresses well, sometimes to 20–40% of the original size. A JPG or MP4 is already compressed, so ZIP may only reduce it by a few percent — sometimes the archive ends up slightly larger because of the ZIP metadata. This is expected behaviour and is not a bug.
Compression levels
Fast (level 1) uses a cheaper algorithm and finishes quickly. Balanced (level 5) is the sweet spot for most tasks. Maximum (level 9) tries harder to find repeated patterns and produces smaller archives for compressible files, at the cost of CPU time. For very large folders — several gigabytes — use Fast to avoid stalling the browser tab.
Common questions
Can I add files from two different folders? Yes. The archive flattens the selection, so files from different folders all end up in the root of the ZIP unless you use the folder picker, which preserves relative paths.
Is there a size limit? The practical limit is your browser's available memory — usually a few gigabytes. For very large archives, split the files into batches.
Are my files uploaded? No. Everything happens in your browser.