Leanify is a file minifier, a lightweight tool which can cut file sizes without affecting the core content (image files are smaller but their quality remains the same, for example).

We’ve discussed similar tools before, in particular FileOptimizer, but Leanify is, well – a little different.

The program appears to support a good range of formats: APK, Office 2007-2013 (DOCX, XLSX, PPTX), DWF/ DWFX, EPUB, FB2/ FB2.zip, GFT, GZ/ TGZ, ICO, JAR, JPEG, LUA/ LUAC, ODT/ ODS/ ODP/ ODG/ ODF, PE (EXE, DLL, SYS, OCX, SCR, CPL), PNG, RDB, SWF, SVG/ SVGZ, TAR, XML/ XSL/ XSLT, XPI, XPS/ OXPS, ZIP.

This isn’t quite as impressive as it looks, because many of these formats are structured in the same way. APK, CBZ, Office/ OpenOffice documents and JARs are all ZIP-based, for example, and so Leanify applies the same tweaks to them all.

Optimising files is easier than it looks, but beware – the originals are overwritten by default

These individual options may not achieve much, either. They’ll strip out a little metadata, simplify headers, maybe recompress a data stream to try and make it more efficient. Sometimes results will be good – images might shrink by 10-20% – but sometimes they’ll achieve precisely nothing at all.

Still, if you must have the smallest possible file – optimising bandwidth usage on a website, say – then Leanify may be able to help. Especially as the program compresses the contents of files, as well as the files themselves (the JPEGs within an APK within a ZIP).

Leanify is a console-based tool, which makes it a little trickier to use. But only a little. Right now your main command line options look like this:

Usage: Leanify [options] path1 path2 path3 …
 -i <iteration> More iterations means slower but better result. Default: 15.
 -d <max depth> Maximum recursive depth.

Not too much to learn, and at a minimum you can just drag and drop a file onto Leanify.exe and watch as it’s compressed.

Be very careful, though. Any files passed to Leanify are overwritten by default, and although the program does its best not to cause any harm, some optimisations may present problems. Always work with copies of files, never the originals, and test the optimised versions carefully to confirm they work as you expect.