Pack and unpack ZIP files without uploading anything
Drop files or entire folders, pick how hard to compress, and get a standard ZIP. Or open an archive, browse it like a file manager and pull out only what you need.
Drag files or folders here
Dropped folders keep their structure inside the archive. Nothing is compressed until you press the button.
Archive settings
How it works
Drop files or whole folders
Folders keep their structure. Nothing is packed yet — the queue just waits for you.
Choose how hard to squeeze
Five presets, or set the method file by file in manual mode.
Press the button
A worker thread does the packing, so the page keeps responding and you can cancel.
Download or keep working
Save the archive, or send a file straight to another oLoveTools tool.
Packed off the main thread
Compression runs in a Web Worker with live progress and a working cancel button. The page never freezes, however big the queue is.
Compression decided per file
Smart mode deflates what compresses and stores photos, video and other packed formats raw — same size, a fraction of the time.
Folders survive the trip
Drop a directory and its structure lands inside the archive intact. Rename any entry before packing, undo and redo as you go.
A real archive explorer
Sizes, ratios and dates come from the ZIP directory, so a 2 GB archive lists instantly. Preview text, images, audio and video without extracting everything.
Nothing leaves the tab
No upload, no server, no account. The files stay in memory and disappear when you close the page.
Straight into the next tool
Send a file from inside an archive to the background remover, the image compressor or the JSON explorer without a round trip through your downloads folder.
A ZIP compressor and extractor that never uploads your files
Most online ZIP tools send your documents to a server, compress them there and hand back a download link. ZipFlow does the whole job in your browser: the archive is built in a worker thread on your own machine, and the bytes never touch a network.
Compression on a worker thread
Deflating hundreds of megabytes on the main thread freezes the tab: no scrolling, no progress, no way out. ZipFlow moves the work to a Web Worker, so the interface keeps repainting, the progress bar tracks real bytes, and cancelling actually stops the job.
A file manager for archives, not a black box
Bundle a client delivery with its folder structure, check what an unknown .zip actually contains before extracting it, pull one photo out of a backup, or inspect the inside of a .docx, .jar or .apk — they are all ZIP containers.
There is no upload endpoint to trust. Your contracts, source code and photos are read, compressed and written entirely inside the tab, and nothing survives closing it.
Frequently Asked Questions
QAre my files uploaded anywhere?+
No. Both compression and extraction run on your own machine, inside this tab, using the JSZip library in a Web Worker. There is no upload endpoint in the tool at all.
QCan I compress a whole folder?+
Yes. Use "Add a folder", or drag the folder onto the drop zone — the directory structure is rebuilt inside the archive. You can rename any entry before packing, and undo the change with Ctrl+Z.
QCan it open password-protected archives?+
No, and it will tell you so instead of failing silently. ZIP encryption is not supported by the library ZipFlow is built on, so an encrypted archive is reported as such the moment you open it.
QWhat does "Smart" compression actually do?+
It picks the method per file. JPEG, PNG, MP4, MP3 and other formats are already compressed, so deflating them costs CPU and saves almost nothing — those are stored raw, and the effort goes into the files that genuinely shrink. Use "Compare all five presets" to see the numbers on your own files.
QWhy are filenames in old archives sometimes garbled elsewhere but not here?+
A ZIP entry either flags its name as UTF-8 or leaves raw code page 437 bytes. Most tools run UTF-8 over both and mangle the second kind. ZipFlow tries UTF-8 first and falls back to CP437, so accented and non-Latin names from old packers come out readable.
QHow big an archive can it handle?+
The limit is your browser's memory, because the archive is held in RAM rather than streamed to disk. A few hundred megabytes is comfortable on a normal machine; multi-gigabyte archives may run out of memory, and ZipFlow says so rather than hanging.