Protect PDF with Password

Q: Is the password protection actually secure?

Yes. Encryption is applied using AES-256, the same standard used by Adobe Acrobat, financial institutions and government agencies. Without the correct password, the encrypted bytes are computationally infeasible to break with modern hardware, and there is no backdoor or master key that bypasses it.

Q: What is the difference between Open Password and Permissions Password?

An Open Password (User Password) encrypts the whole document and prevents it from being opened at all without entering it first. A Permissions Password (Owner Password) allows the file to be opened and read freely, but blocks specific actions such as printing, copying text, or editing. Both can be applied together for full control.

Q: Are my uploaded files stored on your servers?

Files are temporarily uploaded to process the encryption and generate the download link, then deleted automatically and permanently, typically within the same session and always within one hour. Document contents are never read, shared or retained.

Q: What if I forget the password I set?

There is no recovery mechanism by design, which is what makes AES-256 encryption reliable. Always store the password in a password manager before protecting the file, since it cannot be retrieved from the encrypted PDF afterwards.

Q: Can I restrict printing but still let people read the PDF?

Yes. Choose Permissions Only or Full Protection and enable the Disable Printing restriction. Recipients can open and read the document normally, but the print option is blocked in compliant viewers.

Q: Is there a file size limit for protection?

The tool supports PDF files up to 100 MB. For larger documents, split the file into sections first, then protect each part separately.

Encrypt your PDF with AES-256 to prevent unauthorized access. Optionally restrict printing and editing — free, fast, and secure.

Select PDF File

or drag & drop your PDF here

Up to 100 MB • Free forever

Requires a password to open and view the PDF at all.

Password

Confirm Password

Restrict the following actions

Disable Printing Disable Copying Disable Editing

AES-256 encryption

No files stored

No watermarks

What This PDF Protector Does

This tool encrypts your PDF using AES-256, the same standard used by Adobe Acrobat. You can require an Open Password to gate access entirely, apply Permission restrictions to block printing, copying, or editing while still allowing the file to be opened, or combine both for full control.

The encrypted file is generated in seconds and deleted from Convixy's servers immediately after download, always within one hour. There's no watermark, no account, and no limit on how many files you can protect.

AES-256 encryption

Industry-standard encryption makes the PDF unreadable without the password.

Permission controls

Restrict printing, copying, or editing independently, or all together.

Dual-mode protection

Set an open password, permissions only, or combine both for maximum control.

Strength indicator

A live meter guides you toward a strong, secure password.

Tips for Strong PDF Password Protection

Use at least 12 characters mixing uppercase, lowercase, numbers, and symbols — length matters more than complexity alone.
Avoid names, dates, or dictionary words. A passphrase like Sunset!River#42 is both strong and memorable.
Store your password in a password manager before locking the file — there is no recovery if you forget it.
For shared documents, use Permissions Only so recipients can read without a password but can't print or edit.
Need to revoke access? Use Unlock PDF on the file and re-protect it with a new password.

Frequently Asked Questions

Is this PDF password protector completely free?

Yes, completely free with no hidden conditions. There is no watermark added to the encrypted PDF, no account or payment information required at any stage, and no cap on how many files you can protect per day or per month. Convixy's tools are funded by advertising, not by paywalls or usage fees.

The only constraint is a technical one designed to keep the service fast and reliable for everyone: a maximum file size of 100 MB per upload. The vast majority of PDF documents — contracts, invoices, reports, scanned forms — fall well within this limit. For image-heavy files that approach it, running the document through Compress PDF before encrypting usually brings it comfortably under the cap.

Is the password protection actually secure?

Yes. Encryption is applied using AES-256, the same standard used by Adobe Acrobat, banks, and government agencies for classified and financial data. Once encrypted, the file's content is stored as ciphertext — without the correct password, the bytes on disk are mathematically unreadable, and there is no shortcut, backdoor, or master key that bypasses this on our end or anyone else's.

Security in practice also depends on the strength of the password you choose. A short or common password can still be guessed through brute-force or dictionary attacks even with strong encryption underneath it, so the real-world security of your file is only as strong as the password protecting it. The strength meter on this page is there to help you avoid that weak link — aim for at least 12 characters with a mix of character types, as covered in the tips above.

What's the difference between Open Password and Permissions Password?

An Open Password (also called a User Password) encrypts the entire document and prevents it from being opened at all without entering it — the viewer shows a password prompt the moment someone tries to launch the file. This is the stricter of the two protections and is the right choice for confidential documents you're sending to a specific recipient who needs the password to get in at all.

A Permissions Password (also called an Owner Password) does not block the file from being opened — anyone can view it freely. Instead, it enforces restrictions on what the reader is allowed to do once inside: printing, copying text, editing, and form-filling can each be independently disabled. This is commonly used for distributing read-only reports, contracts, or course materials where you want people to be able to read the content but not alter, extract, or print it. Choosing Full Protection on this page applies both at once, for maximum control.

Can I remove the password later?

Yes. Use the Unlock PDF tool, enter the password you originally set, and download a fully unrestricted copy with the encryption layer removed. The content of the document itself is completely unaffected by either locking or unlocking — only the encryption wrapper changes.

If you want to change the password rather than remove it entirely, the process is the same: unlock the file first, then re-upload the unlocked copy here and apply a new password. This is useful if a password has been shared more widely than you'd like and you want to revoke access — the old password becomes instantly useless on the newly protected file.

Are my uploaded files stored on your servers?

Files are temporarily uploaded purely to run the encryption and generate your download link. Both the original upload and the encrypted output are deleted automatically and permanently from Convixy's servers, typically within the same browsing session and always within one hour. There is no manual deletion step required on your part.

We do not read, index, analyse, or share the contents of your documents under any circumstances, and no account is required — so there's no user profile your files could be linked to. All transfers happen over an encrypted HTTPS connection, and the password you set is used only to run the encryption command; it is never logged or stored separately from the file.

What if I forget the password I set?

There is no recovery mechanism, and that's by design — it's exactly what makes AES-256 encryption trustworthy. If a lost password could be recovered by us or anyone else, the encryption wouldn't be providing real protection in the first place. Once the file is encrypted, we have no way to retrieve, reset, or bypass the password on your behalf.

Because of this, always save the password to a password manager such as Bitwarden, 1Password, or KeePass immediately after setting it, before you close the tab or share the file. If you do lose access to a protected PDF and have no record of the password, there is no legitimate free tool that can reliably break modern AES-256 encryption — the practical options are to recreate the document from another source, or to check whether an earlier unprotected version still exists elsewhere.

Can I restrict printing but still let people read the PDF?

Yes. Select Permissions Only or Full Protection, then check Disable Printing in the restriction options. Recipients can open and read the document normally with no password prompt, but the print option is greyed out or blocked in their viewer once they try to use it.

The three restriction checkboxes — printing, copying, and editing — are independent, so you can mix and match. For example, you might allow printing while disabling copying and editing, which is common for distributing forms that people need a paper copy of but shouldn't be able to alter digitally. This is frequently paired with an Open Password for documents that need both access control and usage restrictions.

How is PDF password protection different from compressing or watermarking?

Compression reduces file size by optimising embedded images and internal streams — the content stays fully accessible and unencrypted throughout. Watermarking stamps visible text or an image onto the pages themselves, permanently altering what's rendered. Password protection is different again: it encrypts the actual bytes of the file so they're unreadable without decryption, without changing anything about how the pages look once opened.

These operations are independent and often used together. A common workflow is to compress a large file first, add a watermark to mark it as a draft or confidential, and then apply password protection last so the final distributed file is small, clearly marked, and access-controlled all at once.

Do permission restrictions work in every PDF viewer?

Permission restrictions are part of the official PDF specification and are respected by all compliant viewers, including Adobe Acrobat, macOS Preview, Foxit, and most mobile PDF apps. When printing or copying is disabled, these applications grey out or block the corresponding action as soon as the user tries to use it.

That said, restrictions rely on the viewer choosing to enforce them rather than on encryption of the visible content itself — a small number of non-standard or open-source viewers may not honour them strictly. For situations where you need a hard guarantee that unauthorized users can't even open the file, combine Permissions restrictions with an Open Password using Full Protection, since the Open Password is enforced through encryption rather than viewer cooperation.

Is there a file size limit for protection?

The tool supports PDF files up to 100 MB, which covers the overwhelming majority of everyday documents including scanned contracts, multi-page reports, and image-heavy presentations exported to PDF. Encryption itself adds negligible overhead to the file size, so the protected output is roughly the same size as the original.

For documents that exceed the limit — typically very large scanned archives or design-heavy files — use Split PDF to divide the file into logical sections first, then protect each part separately. Alternatively, run the file through Compress PDF beforehand to shrink it below the threshold without a noticeable quality loss, then encrypt the smaller result here.