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PDF Password Protect & Unlock

Add password protection to a PDF or remove it from one you own. Set separate user and owner passwords, control printing and copying permissions, and unlock a protected file with its password.

Everything runs locally in your browser. Your data never leaves your device.

PDF

Drop a PDF here

Protect it with a password, or unlock a protected one. Click to choose a file.

Up to 512 MB.

Passwords

Left empty, the open password covers both jobs. Set a separate one so people who may open the file still can't lift the permission limits.

There is no password recovery. If the password is lost, the PDF stays locked.

Encryption & permissions

The current standard. It needs a modern reader, Adobe Reader X from 2010 or newer, and every current browser viewer handles it.

PDF readers enforce these limits, they are a convention that well-behaved software honors, not cryptography. The content itself is what the password encrypts.

Add a PDF first.

Next steps

Send this tool's output straight into another tool.

PDF Compressor

Shrink a PDF's file size by re-encoding its pages at a chosen quality and resolution. See the size before and after, preview the result, and tune the quality until size and readability balance.

pdfcompress

PDF Merger & Splitter

Combine several PDFs into one or split a PDF into separate files. Reorder pages with drag and drop, see a thumbnail of every page, extract a page range or pick single pages, and download the result.

pdf

Hash Generator

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

devsecurity

Checksum Validator

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

devsecurity

Data Compressor

Compress text or a file with gzip, deflate, brotli or Zstandard and see the size before and after, the compression ratio and how long it took. One click tries every method and recommends the smallest result.

devcompress

Data Decompressor

Decompress gzip, deflate, brotli or Zstandard data from a file or pasted Base64 and read the result as text or download it. Detects the format from the magic bytes where possible, with a manual override.

devcompress

Hex Viewer

Inspect any file or text as a hex dump with offsets, byte values and an ASCII column. Jump to an offset, search for bytes or text, select a range to see it decoded as integers and strings, and copy or download the dump.

dev

PDF to Images

Render every page of a PDF as an image. Choose PNG or JPEG, set the resolution, pick single pages or a range, then download pages one by one or all at once as a zip.

pdfimageconverter

File Encryptor & Decryptor

Encrypt any file with a password using AES-256-GCM, or decrypt a file that was encrypted here. Strong key derivation and integrity protection built in.

security

About the PDF Password Protect & Unlock Tool

This tool puts a password on a PDF or takes one off. Protect mode encrypts the file with AES so it only opens with the password you set, with an optional separate owner password and permission limits for printing, modifying, copying and annotating. Unlock mode removes the protection from a PDF you can open and gives you a copy that works without a password.

Drop a PDF in and the right mode is picked for you. An encrypted file opens in Unlock, everything else in Protect. The work is done by qpdf, the same engine many server-side PDF pipelines rely on, compiled to WebAssembly.

What you can do

  • Password protect a PDF before sending it by email.
  • Remove the password from a PDF you own so it stops asking on every open.
  • Set a separate owner password that controls permission changes.
  • Restrict printing, modifying, copying and annotating in a PDF.
  • Choose AES-256 encryption, or AES-128 for very old readers.
  • Strip print and copy restrictions from a PDF that opens without a password.

How to use the PDF Password Protect & Unlock

  1. 1Drop the PDF in, or pick it with a click. Protect or Unlock is preselected from the file itself.
  2. 2To protect, type an open password and confirm it, optionally add an owner password, then pick the encryption strength and the permissions.
  3. 3To unlock, type the password the PDF currently opens with. Leave it empty for a file that only restricts printing or copying.
  4. 4Press Protect PDF or Unlock PDF, then download the result.

Open password and owner password

The open password, called the user password in the PDF spec, is what a reader asks for before showing the document. The owner password is what allows changing the encryption and permission settings later. Left empty, the open password covers both jobs. You can also set only an owner password, then the PDF opens for everyone but the permission limits apply and changing them needs the owner password.

There is no password recovery. If the password is lost, the PDF stays locked, so pick one you can keep. The Password Generator can make you a strong one.

AES-256 or AES-128

AES-256 is the current standard and the default. It needs a modern reader, Adobe Reader X from 2010 was the first Adobe version to open it, and every current browser viewer handles it. Pick AES-128 only when the file must open in very old software, it goes back to Adobe Reader 7. Both choices always use AES, the tool never writes the outdated RC4 encryption.

What unlocking does and does not do

Unlock is for PDFs you are authorized to open. It takes the password the file already opens with and writes a copy without encryption. That includes PDFs that open without any password but block printing or copying, for those the password field just stays empty. It does not guess, crack or recover unknown passwords. A wrong password produces a clear error and nothing else.

Permissions are a convention

The permission limits for printing, modifying, copying and annotating are enforced by PDF readers, not by the encryption itself. Well-behaved software honors them, but tools exist that lift them. Treat them as a strong signal of intent, and rely on the open password when the content itself must stay private.

Send the result onward

The protected or unlocked copy can go straight to another PDF tool, for example the PDF Compressor to shrink it or the PDF Merger & Splitter to combine it with other files.

Credits

Open source does the heavy lifting in this tool. Thank you to:

  • qpdf

    A command-line program and library that does structural, content-preserving transformations on PDF files, including encryption.

Everything this site builds on is listed on the credits page.

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Checksum Validator

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

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Images to PDF

Turn photos and images into a single PDF. Drop in JPEG, PNG or WebP files, reorder them, pick the page size, orientation and margins, and choose whether each image fills the page or keeps its own size.

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