Smallpdf

What it does

Smallpdf does the same core operations as everyone else — compress, merge, split, convert, sign — with by far the least cluttered interface, which matters when you are talking a colleague through it over the phone. Its 'strong' compression downsamples embedded images and usually halves a scan. The free plan is strictly rationed and it will tell you so halfway through the task.

Best for

• Shrinking a scanned document
• Walking someone non-technical through a PDF job

Where it stops