How to remove a password from a PDF when you know it
If you know the password, you can save an unlocked copy in under a minute. Here are four ways, from free built-in tools to a verified online copy, and when each one fits.
Option 1: Chrome, Edge or Firefox (free)
Open the PDF in the browser, enter the password, then choose Print and set the destination to Save as PDF. The new file has no password. Because it is re-created by printing, links, bookmarks, form fields and some accessibility tags may be lost, and very large files can be slow.
Option 2: Preview on a Mac (free)
Open the PDF in Preview, enter the password, choose File > Export, and untick Encrypt in the dialog. Save under a new name. This keeps text and images as they are in most files.
Option 3: Adobe Acrobat (paid)
Open the file and enter the password, then use File > Properties > Security and set the security method to No Security, then save. This edits the original structure rather than re-printing it.
Option 4: UnsealPDF
Add the file, enter the password, and UnsealPDF removes it and checks the result against your original: the copy opens without a password, the page count matches, and every stored object is identical apart from the encryption. You see the checks before you pay. From $1.99 per job, charged only after the result is verified. It also handles several files at once. It does not guess or recover passwords. Limits: up to 20 MB per file, 10 files and 500 pages per job.
Which should you choose?
For one personal file, the browser or Preview method is free and usually enough. Use a verified copy when the file must stay structurally intact (forms, tagged text, signatures excepted), when you have several files, or when you want proof the unlocked copy matches the original.
If the PDF has a signature
Any rewrite, by any tool, invalidates digital signatures. If the signature must remain valid, keep the original and do not unlock it.
Questions
Can I remove a PDF password without knowing it?
Not legitimately. Modern PDF encryption cannot be removed without the password, and UnsealPDF does not guess, crack or recover passwords. Ask whoever set it.
Is removing a PDF password legal?
Removing a password from a file you own, or have permission to open, is normal. Do not remove protection from files you are not allowed to change. This is not legal advice.
Does the unlocked PDF look the same?
The content is the same. Printing to a new PDF can lose links and form fields; Preview, Acrobat and UnsealPDF keep the document's structure.