Jonathan Kew made a nice tool to create WOFF fonts very easy.
Just install/compile it and run:
sfnt2woff font.ttf
As you can see the size of a WOFF file is similar in size to a compressed TTF file.
For example take the free Ubuntu-Regular font:
Size
- TTF: 345 KB
- WOFF: 165.8 KB
- gzipped TTF: 169 KB
The downside of a WOFF is that you can’t install it locally, so you can’t speed up your favourite website by installing its beautiful fonts as a desktop font.