Supported file
Use one readable, unencrypted PDF up to 20 MB and 500 pages. Protection uses the standard AES-256 PDF security handler. Do not use this for files requiring legacy-reader compatibility.
Protect a PDF with a password.
Apply real PDF password encryption before sharing. Choose a unique passphrase and download a copy that compatible PDF readers require a password to open.
Processed in your browser · No account · No upload
Encrypt the document before sharing.
File and password stay on this device
Choose a PDF
One PDF · up to 20 MB · maximum 500 pages
Choose a PDF fileSelect a readable PDF from this device.
Use a unique passphrase with at least 12 characters; 16 or more is better. Avoid names, common phrases, and passwords used elsewhere. Passwords are not checked online or saved by EkkySoft.
Choose one PDF to get started.
Processing uses QPDF WebAssembly in a temporary browser Worker. Your PDF and password are not uploaded, sent to analytics, or saved to browser storage. The password field is cleared after each attempt.
Protect a PDF with a password
- Choose a PDF.
Select one readable, unencrypted PDF up to 20 MB and 500 pages.
- Set and confirm a passphrase.
Use a unique passphrase of at least 12 characters. A longer passphrase is safer; EkkySoft cannot recover a forgotten password.
- Encrypt and verify.
The file is encrypted with the PDF standard AES-256 handler. The output is checked with the entered password before download.
Local processing
The PDF and password are held temporarily in browser memory and processed by QPDF WebAssembly in a temporary Worker. Neither is sent to EkkySoft or analytics or saved to browser storage.
Document limitations
Protection encrypts PDF strings and streams with AES-256; it is not a substitute for safe password sharing. Decryption and encryption rewrite the document, invalidating digital signatures. Never use PDF permission flags as a substitute for encryption.
Questions and troubleshooting.
Is this real password protection?
Yes. QPDF writes standard PDF AES-256 password encryption. The output is not a renamed file or a screen overlay; a PDF reader must decrypt the document using a compatible password.
Will every PDF reader open the result?
No. AES-256 uses the modern PDF 2.0 encryption handler. Use a current PDF reader; older software may not support this format.
What if I forget the password?
EkkySoft does not store or recover it. Keep a safe copy of the passphrase before encrypting your only copy.
Are my file or password uploaded?
No. QPDF runs in a temporary browser Worker. The file and password are not sent to EkkySoft, analytics, or browser storage.
Will signatures remain valid?
No. Rewriting a digitally signed PDF invalidates its signatures. Keep the original signed document unchanged.