Zlib, Zopfli and Brotli
compression comparison
You might want to read about the tradeoffs for using those tools to (pre)compress HTTP content.
Drop a file here
or
to compress it.
or
to compress it.
The compression is done in your browser and the file is never sent out or even saved in the browser storage.
Warning: Zopfli compression is quite slow. Be prepared to wait a while for large files.
You can also try it on the wasm file that does the brotli compression, or on the html file of the full page.