PDF answers
Short, direct answers to the questions that come up before you trust a document to a tool: what is safe to upload, why files get big, and what the different PDF standards mean.
Is it safe to upload PDFs to online tools?
What really happens to your file when a PDF site asks you to upload it.
Are online PDF tools safe?
How to judge whether a browser PDF tool is safe, and what to watch for.
Why is my PDF so large?
The real reason PDFs get big, and what actually shrinks them.
What is a PDF/A file?
The archiving flavour of PDF, what it guarantees, and when it is required.
Is an electronic signature legally binding?
When a signature added on screen counts, and when it does not.
How do I split a PDF into email-friendly parts?
Cut a too-large PDF into pieces that each fit an email limit.
The tools
Every tool runs entirely in your browser. Files are never uploaded, and once a page has loaded it keeps working offline.
Want step-by-step instructions instead? See the PDF guides.