JPEGmicro is a free tool which rewrites JPEG files to reduce their size.

The program looks great. There's a sleek, black interface, panels slide out smoothly while flat buttons carry out its main actions.

Getting started is as simple as hitting the add button and choosing your source images (or just dragging and dropping them onto the program).

Tapping the Options icon shows various compression settings. You can remove EXIF/ XMP tags, strip out the ICC colour profile, rewrite the file as a progressive JPEG, maybe reduce its quality to really crunch down those file sizes.

There's also good control over the name and location of the destination files, with options to rename them, save them to a new folder, overwrite the originals, and more.

The default lossless compression made little difference to our test web graphics, unsurprisingly. Most images were unchanged, the tags it found weren't taking much space, and overall our 50 files fell from 412KB to 403KB in size.

Using the default lossy compression level of 75 cut our files by around 30%, but also reduced image quality. You'll need to experiment to see if this is acceptable, and what the right levels are for you.