PDF
Compress PDF
For upload limits: shrink the images, keep text sharp.
Drop PDFs here
Works best on scans and slide decks with lots of photos.
Or paste with Ctrl + V
Good to know
Mostly the images get smaller: they are scaled down and recompressed. Text and vector graphics stay sharp. A PDF that’s only text barely shrinks.
Scan mode
For scanned pages. Each page is split into three layers, as professional scanning software does: the lettering as a sharp black-and-white mask at full resolution, plus its colour and the paper with photos and highlighter, both heavily reduced. The text stays crisp and the file often ends up ten times smaller than with normal compression.
Pages with real, selectable text (from Word, say) are left untouched. Text recognition already contained in a scan is kept.
The first run downloads the program for this (about 11 MB). After that it works offline too.