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How to open a .pdf file

Portable Document Format · Document

Every operating system and browser opens PDFs natively. If yours will not open, it is almost always password-protected, and there are two different passwords with very different consequences.

What a .pdf file actually is

PDF was created by Adobe in 1993 and became an open ISO standard in 2008. It fixes layout, fonts and images so a document looks identical everywhere, which is exactly why it is used for contracts, forms and anything that must not reflow.

The reason people search for help is rarely the format itself. It is the security layer: PDF supports two separate passwords and most guides conflate them.

Why it will not open

A PDF can carry a user password, which is required to open the file at all, and an owner password, which allows opening but blocks printing, copying or editing. If you are prompted before you see anything, that is the user password and you need it from the sender. If the file opens but printing is greyed out, that is the owner password.

Renaming it to an extension you can open will not help: changing the extension does not convert the file, it only changes what Windows tries to open it with.

Step by step

Windows

  1. 01Try double-clicking first. Edge, Chrome and Firefox all render PDFs without any software.
  2. 02If you are asked for a password before the document appears, only the sender can supply it. No legitimate tool bypasses a user password.
  3. 03If it opens but editing or printing is blocked, that is an owner password. In many viewers you can print to PDF, creating an unrestricted copy of a document you are already allowed to read.
  4. 04For a PDF that renders as blank pages, the file uses an XFA form built for Adobe Acrobat. Open it in Acrobat Reader specifically; browsers cannot render XFA.

macOS

  1. 01Double-click. Preview opens PDFs natively.
  2. 02To remove owner restrictions from a document you are entitled to use, open it in Preview and choose File, Export as PDF.
  3. 03For XFA forms, install Adobe Acrobat Reader, because Preview shows those as a "please wait" placeholder page.

What usually goes wrong

The "please wait" page that never goes away

A PDF that shows only a message asking you to update Adobe Reader is an XFA form, a dynamic format only Acrobat renders. Your software is not out of date. Open it in Acrobat Reader and it works.

Two passwords, two different situations

Removing an owner password on a document you legitimately hold is normal practice. Cracking a user password on a document you were never given access to is not, and tools that advertise it are frequently malware.

Programs that open .pdf

Our pick, in order. Every one links to the publisher's official download URL and the SHA-256 hash of the installer. Once you have downloaded it, you can check the file against our index before you run it.

If you end up downloading one of these from somewhere other than the publisher, what you can and cannot verify about that is worth two minutes.

Also registers .pdf in its manifest

Taken straight from publisher manifests. Some of these handle the format for a narrow purpose rather than as their main job.

Common questions

How do I open a password-protected PDF?
If the password is requested before the document appears, it is a user password and only the sender can give it to you. If the file opens but printing or copying is blocked, that is an owner password, and printing to PDF from your viewer produces an unrestricted copy.
Why does my PDF show "Please wait… if this message is not replaced"?
The file is an XFA dynamic form, which only Adobe Acrobat Reader can render. Browsers and Preview show the placeholder instead. Open it in Acrobat Reader.
What is the best free PDF reader?
SumatraPDF is extremely fast and lightweight on Windows. Adobe Acrobat Reader is necessary for XFA forms and advanced signatures. On macOS, Preview is already installed and handles almost everything.

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