Add a password to a PDF so only people who know it can open it. The file is encrypted with AES-256, the same encryption Adobe Acrobat uses, and you can also block printing, copying or editing. Free, no signup, and your PDF never leaves your browser.
No PDF yet. You can also drop a file on this box.
People who open it may:
| Option | What it does |
|---|---|
| Password | The open password. Nobody can view the pages without it, in any PDF reader. There is no way to recover it if you lose it, so store it somewhere safe. |
| Print, copy, edit | Untick to stop people who know the password from printing, copying text or changing the file. Acrobat, Chrome, Edge and Preview respect these flags; some free tools ignore them. |
| Owner password | Opens the file with full rights, so you can print or edit it even when others can't. Left empty with a box unticked, a random one is used and the limits can't be lifted later. |
| Encryption | AES-256 works in every current reader (Acrobat 9 and later). AES-128 only for very old software. |
Email attachments get forwarded, cloud links get shared, and laptops get lost. A password means a payslip, contract, medical report, tax return or ID scan can only be read by people you give the password to. Send the password through a different channel than the file (a text message or a call, not the same email), or the protection is only for show. Many companies and accountants also require encrypted PDFs for personal data.
The page uses @cantoo/pdf-lib, an open-source fork of pdf-lib, to encrypt every page, image, font and text string of the PDF with the standard PDF security handler (revision 6, AES-256, the method Acrobat uses since version X). The content itself is not changed: the protected file looks exactly like the original once it is opened. We checked the output with qpdf and poppler, the PDF engines used by Linux and many print systems: every page, link and text string matches the original. Everything happens in JavaScript on this page, so the file and the password are never sent anywhere.
To remove the password later, use Unlock PDF. To hide parts of a document before you share it, redact it; to strip the author and software details, remove its metadata.
If your PDFs come from web pages or HTML templates (invoices, reports, statements), the Shotmint API renders them in Chromium with real, selectable text:
curl "https://shotmint.creasework.com/v1/pdf?url=https://example.com&format=A4" -H "X-API-Key: YOUR_KEY" -o page.pdfEach render is 1 credit. €5 buys 2,000 with no subscription, and credits never expire. Try HTML to PDF or URL to PDF without a key.
Get 25 free renders a month API docs
Is my PDF uploaded? No. Everything runs in JavaScript on this page. The file and the password never leave your device, which is the point for a document worth protecting.
How secure is it? AES-256 with a strong password can't be brute-forced. A short or guessable password (a name, a date) can be, so use at least 10 characters or a few random words.
Will it open on a phone or in Chrome? Yes. Acrobat Reader, Chrome, Edge, Firefox, macOS and iOS Preview, and Android PDF viewers all open AES-256 PDFs and ask for the password.
Can I remove the password later? Yes, with Unlock PDF or Acrobat, as long as you know it.
Is there a size limit? No limit and no watermark. Very large files (hundreds of MB) depend on your device's memory.
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