PDF Tools
Protect PDF
Add a password to a PDF so it can't be opened without it.
- Free to use
- No sign-up
- Instant download
Your file is processed securely and automatically deleted from our servers within 1 hour.
Working on it…
Processing your file — the download starts automatically when it’s ready.
Your file downloads automatically
Choose your file above and run the tool — the result is sent straight to your browser.
About this tool
Lock a document with a password so only people you trust can open it. Choose a strong secret, run the tool and download the locked copy.
How to use it
- Upload the file you want to secure.
- Type a strong passphrase.
- Run the tool and download the locked version.
Choosing a strong passphrase
- Use at least 12 characters, mixing words, numbers and symbols.
- Avoid names, birthdays and anything easy to guess.
- Our Password Generator can create a strong one for you.
When it helps
- Payslips, bank statements and tax records
- Contracts and legal paperwork
- Client files and internal business reports
- Medical or personal records sent by email
Sharing safely
Send the secret through a different channel than the file — for example, the file by email and the code by phone or text — so one intercepted message is not enough to open it.
Good to know
Keep it somewhere safe: without it, even you may not be able to open the locked copy. Test the download before sharing it. Different readers handle locked files in slightly different ways. Uploaded files are deleted from our server shortly after processing.
A worked example
An HR officer needs to email salary letters to 20 employees. Each letter is locked with a unique passphrase agreed with the employee and shared in person. Even if an email is forwarded by mistake, the letter cannot be opened by the wrong person.
Ideas that are easy to share but hard to guess
- A passphrase of three or four unrelated words, such as
river-lamp-orange-42. - A random string from our Password Generator, sent by text message.
- Avoid dates of birth, phone numbers or company names.
What the lock does and does not do
The lock stops the file from opening without the right code. It does not stop someone who knows the code from forwarding, printing or copying the contents, so share it only with people who should read the document.
Checklist before sending
- Open the locked copy yourself to test it.
- Send the file and the code through different channels.
- Keep an unlocked original in a secure place.
- Delete old copies you no longer need.
Related tools
- Password Generator – create a strong random secret
- Add Watermark – label a document as CONFIDENTIAL
- Sign PDF – add a signature before locking
Step by step: emailing a payslip safely
- Agree a passphrase with the employee in person.
- Lock the payslip with it.
- Email the locked file.
- Remind the employee never to share it.