Compress a ZIP file — without uploading it
Recompresses the images inside the archive. Nothing uploads.
Recompresses the images inside the archive. Nothing uploads.
ZIP is already a compressed format, which is why running it through another compressor usually achieves nothing. The bytes that make an archive large are rarely the archive's own overhead — they are the files inside, and if those are photos or scans they are already compressed too.
That is the reason "compress zip file to smaller size" is such a common dead end: the standard tools have nothing left to squeeze. Getting a real reduction means going one level down, into the images themselves.
It opens the archive in your browser, recompresses the images it finds inside, and repacks it. The structure is preserved, so what comes out is a valid ZIP that opens normally — just lighter.
Nothing is uploaded. The archive is read from your disk, rewritten in memory, and handed back as a download.
The savings come from recompressing images inside the archive. A ZIP of documents, code or already-optimised files has very little to give.
Yes. It is repacked with its structure intact, so any unzip tool reads it as usual.
No. Everything happens on your own device.