There are hundreds of PDF tools online, but which one when? This guide splits PDF work into five categories and shows the right tool for each — and what to watch for (privacy, watermark, file size) when choosing.
1) Editing and organizing
Merging, splitting, deleting, rotating or reordering pages is the most common need. These tasks are light and, in good tools, run on your device (in the browser) — your file doesn't go to a server and you get an instant result.
Merge PDF — Combine multiple PDFs into one — on your device.
2) Converting
Turning PDF into Word/Excel/PowerPoint or back; getting a PDF as JPG. These are heavy tasks usually done on the server. The key criterion when choosing a converter: how well formatting (layout, tables, fonts) is preserved.
PDF to Word — Convert a PDF into an editable Word document.
3) Optimizing and securing
Reducing file size (compression), adding/removing a password, adding a watermark or page numbers. Compression to email a file and encryption before sharing are common.
Compress PDF — Make your PDF small enough to email.
4) PDF with AI
Summarizing long documents, asking a document questions, extracting data from invoices, or comparing two contracts. In AI tools the file itself usually isn't uploaded; text is extracted and only the text is processed.
Summarize PDF — Summarize a long document in seconds.
5) What to watch for when choosing a tool
- Privacy: Is the file uploaded to a server, or processed on your device? For sensitive documents, prefer on-device processing.
- Watermark: Does the free output get a forced watermark?
- Signup: Does it force an account for a simple task?
- File size/limits: Up to how many MB, how many operations a day?
On PDF Platform, structural tools (merge, split, rotate, scan) run on your device, no forced watermark is added, and most tasks can be done without an account.