PDF Security
Encrypt, unlock, sign, redact and compare PDF documents.
Unlock PDF
Unlock PDF removes password protection from a document when you supply the correct password, producing a copy that opens without prompting; it cannot crack or bypass a password you do not know.
Protect PDF
Protect PDF encrypts your document with AES-256 so it cannot be opened without the password, and optionally sets print, copy and edit permission flags that conforming readers will honour.
Sign PDF
Sign PDF places a visual signature on your document, either as an uploaded signature image or as a typed name, positioned and sized where you want it on the page.
Redact PDF
Redact PDF permanently removes sensitive content by covering the selected region and rasterising the page, which destroys the underlying text so it cannot be selected, copied or recovered.
Compare PDF
Compare PDF extracts the text from two documents, diffs them word by word, and returns a side-by-side HTML report highlighting every insertion, deletion and change.
About these tools
Protection uses AES-256 encryption. Redaction genuinely destroys the hidden content rather than just covering it, which is the failure behind most real-world redaction leaks. Unlocking removes a password you already know — it cannot break encryption.
Every tool in this category is free, needs no account and adds no watermark. Files are processed on our own server and deleted automatically within one hour.