Password protect and encrypt any file
Lock documents, photos, and archives with authenticated AES-256-GCM encryption. Processed 100% locally in your browser — your file never leaves your device.
How it works
Select any file
Choose a PDF, image, document, or archive from your device.
Choose a strong password
Enter a secure passphrase. A strength indicator helps you gauge complexity.
Encrypt in browser
Click Encrypt File to run PBKDF2-SHA256 and AES-256-GCM locally in your browser.
It is processed on your machine
This is the kind of content people are most nervous about pasting into a website. Here nothing is transmitted: your browser reads the input, the tool works on it in the tab, and the result is handed straight back. Close the tab and it is gone.
- Opened from your disk by your browser — not sent anywhere first.
- Held in the tab while the tool works, then dropped.
- Saved to your device by your browser, not by a link to a server.
- Closing the tab clears the working copy completely.
- No account, so nothing is ever attached to an identity.
- No tracking of what you worked on or what was inside the file.
There is no queue and no retention policy to read. Whatever you pasted is released the moment the tab closes. See how your data stays inside the tab for the full picture, or follow the DevTools check to verify your file never leaves.
What people use it for
Formats & limits
What this tool accepts, what it produces, and what it will never ask you for.
- Input
- PDF, PNG, JPG, ZIP, or any file format
- Output
- Set in the controls above
- Maximum file size
- Set by your device, not by a plan
- Files per run
- One at a time
- Sign-up required
- None
- Watermark
- Never added
- Works offline
- Yes, once the page has loaded
- Supported browsers
- Any current Chrome, Edge, Firefox or Safari
When something goes wrong
Invalid input stops with a plain message that points at the exact problem, rather than a spinner that never finishes.
The content is not in the shape this tool expects. Check for a missing bracket or an extra character and try again.
Why not an online service
A hosted version of this tool means your input is transmitted to a server you have no relationship with. Removing that step removes the whole category of risk.
A typical upload site
This tool
Questions
Is my file uploaded to a server?
Never. All encryption runs 100% on your device using the browser's native Web Cryptography API. Your file never leaves your computer or phone.
What encryption standard is used?
We use industry-standard AES-256-GCM with PBKDF2-SHA256 key derivation at 250,000 iterations and a cryptographically random salt and initialization vector.
Can Filezaar recover my password if I forget it?
No. Because encryption runs locally with zero knowledge and zero server storage, there is no master key or password reset. Keep your password safe.
What file formats can I encrypt?
You can encrypt any file format, including PDF, JPG, PNG, DOCX, XLSX, MP4, and ZIP archives.
How do I open an encrypted .fz file?
Use our free Decrypt File tool with your original password to restore the original file and format.
Is there a file size limit?
No fixed limit is imposed by the tool. The practical ceiling is how much memory your device has free, because the whole job runs inside this browser tab.