Protéger PDF
Ajoute un mot de passe (AES-256), retire un mot de passe connu ou répare un PDF endommagé — avec option fast web view.
Password-protecting a PDF encrypts its contents with AES so the file is unreadable without the password — the protection travels with the file, unlike a shared-folder permission that disappears the moment someone forwards it.
There are two distinct passwords in the PDF specification. A user password is required to open the document at all. An owner password leaves it readable but restricts printing, copying and editing; that restriction is a convention that well-behaved readers honour, not a cryptographic barrier. If the content is genuinely sensitive, set a user password.
How it works
- Open the PDF you want to protect.
- Set a password to open the document, and optionally an owner password with permission restrictions.
- Choose which actions to allow — printing, copying text, annotating.
- Download the encrypted PDF.
What people use it for
- Emailing payslips or medical records where the attachment may pass through several inboxes.
- Sending a draft to a reviewer without letting them copy text out of it.
- Distributing internal documentation that must not be printed.
Frequently asked questions
- Is my file uploaded to a server?
- No. The file is opened by JavaScript and WebAssembly running inside your own browser tab. It is never uploaded, there is no server-side processing and nothing is stored — closing the tab discards everything.
- What happens if I lose the password?
- The file cannot be recovered. Encryption is done properly, which also means there is no back door here or anywhere else. Store the password before you close the tab.
- What is the difference between the two passwords?
- The user password is needed to open the file — without it the content is inaccessible. The owner password only restricts actions such as printing or copying in a document that anyone can still open.
- Do the restrictions actually prevent printing?
- In compliant readers, yes. They are enforced by the reader rather than by cryptography, so treat them as a clear statement of intent, not as a security control.
Outils similaires
Signature électronique
Signe cryptographiquement un PDF avec ton certificat P12/PFX (PAdES) — le certificat ne quitte jamais ton navigateur. Signature visible en option.
Déverrouiller le PDF
Retire le mot de passe d’un PDF que vous pouvez déjà ouvrir — vous devez connaître l’actuel. Ne casse pas les fichiers protégés.
Caviarder PDF
Masquez le contenu sensible avec des rectangles permanents dessinés sur la page.
Caviarder par recherche
Saisissez des mots ou des motifs et caviardez toutes les occurrences dans tout le PDF.