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PDF Encryption Checker

Find out whether a PDF is encrypted and how strongly.

  • Free
  • No signup
  • Nothing uploaded
  • No watermark

Read in this tab, and never written to. Nothing is uploaded — which is the point, since inspecting a PDF usually means you do not yet trust it.

How to Use the PDF Encryption Checker Online

PDF Encryption Checker: before and after PDF A BEFORE PDF ENCRYPTIONCHECKER PDF A AFTER

Not every locked PDF is actually protected. This reads the encryption dictionary and reports the algorithm, key length and security revision, then says plainly what that means: 40-bit and 128-bit RC4 are broken and fall to recovery tools, AES-128 is sound, AES-256 is the current standard. If the file is not encrypted at all, it says so, because anyone holding it can read, copy and change it.

Finds out whether a PDF is encrypted and how strongly. Older files use 40-bit or 128-bit RC4, which is now trivially broken; AES-256 is the current standard. If a document genuinely needs protecting, the encryption strength is the part that matters rather than the permission flags.

No software to install Free Works on any device

Step-by-Step Guide to Using the PDF Encryption Checker

  1. 1. Drop your PDF in, or click to choose one

  2. 2. It is read in your browser and the report appears straight away

  3. 3. Nothing is uploaded, and the file itself is never changed

No .pdf file to hand? Download a sample PDF file (6.3 KB) and try it.

Try it now

What is the PDF Encryption Checker?

Finds out whether a PDF is encrypted and how strongly. Older files use 40-bit or 128-bit RC4, which is now trivially broken; AES-256 is the current standard. If a document genuinely needs protecting, the encryption strength is the part that matters rather than the permission flags.

PDF file

.PDF

Find out whether a PDF is encrypted and how strongly.

At a glance

  • Takes: .pdf
  • Gives: Encrypted yes or no, algorithm, revision R2–R6, algorithm version, key length in bits
  • Verdict: RC4 flagged as broken, AES-128 as sound, AES-256 as current
  • Also: A note that password length is what protects an AES-256 file
  • Runs: Read in the browser tab; the PDF is never uploaded
  • Price: Free, no signup

Why Inspect a Document Before Sending?

A file can look fine on screen and still fail a portal check because of its version, page size, fonts or hidden permissions. Inspecting it first shows those details plainly, and the helper tools split, merge and shrink data and office files.

“Check the file before someone else rejects it.”
  • Page count and size at a glance
  • Version and standard checks
  • Hidden attachments brought out
  • Data files split or merged
  • Fonts and links listed
  • Permissions shown before you share
  • Office files made smaller
  • Excel formulas explained

Popular Uses for Document Checkers

These checks answer the questions people have about a file before it goes anywhere.

  • Print shop checks Confirm page sizes, orientation and PDF/X before sending artwork to a printer.
  • Archive submissions Check whether a PDF meets PDF/A before submitting it to a court or registry.
  • Counting pages and words Find the page count and word count of a PDF for a quote or limit.
  • Checking links List every link inside a PDF to find broken or outdated addresses.
  • Font problems See which fonts a PDF uses and whether they are embedded for printing.
  • Shrinking Office files Make a heavy Word, Excel or PowerPoint file smaller before emailing it.
  • Splitting large CSVs Cut a huge CSV or JSON file into parts that other tools can open.
  • Excel formula help Check a formula for errors or turn a column number into its letter.

What You Can Do with the PDF Encryption Checker

Understands PDF structure rather than treating the file as bytes

Validation happens on your own machine, at your machine's speed

Reports what the file actually declares — fonts, permissions, encryption and PDF/A conformance

Reads the structure without rendering, so a file that crashes a viewer can still be examined

Why Use ToolXkit for PDF Encryption Checker?

Your files stay with you

Everything runs inside your browser. Nothing you open or type is uploaded to a server.

Document Inspection for Different Users

Printers and publishers

Check PDF/X, page sizes and fonts before a job goes to press.

Legal professionals

Confirm PDF/A compliance, page counts and permissions before filing documents on a court portal.

Translators

Count words in a PDF to quote a fair price for a translation.

Data analysts

Split, merge and count rows in CSV and JSON files too big to open.

Office administrators

Check file sizes, versions and security settings before uploading to portals.

Web teams

Extract links and bookmarks from PDFs before publishing them on a website.

Best Times to Check a PDF or Data File

Inspection tools are worth a look when you are:

  • Sending artwork to a printer
  • Filing papers on a court portal
  • Quoting a translation job
  • Opening a CSV too big for Excel
  • Checking why a PDF was rejected
  • Sharing a file with restrictions
  • Emailing a heavy PowerPoint deck
  • Auditing links in a brochure

Tips and Good to Know

  1. It tells you how strong the lock is; it does not open it. To remove a password you know, use Unlock PDF.

  2. A strong algorithm with a short password is still weak. AES-256 with a six-character password falls to a dictionary attack, and this cannot test the password.

  3. Permission flags for printing and copying are a separate question. Use PDF Permission Checker for those.

Frequently Asked Questions

Answers to common questions about this tool.

Do I need to install anything to use the PDF Encryption Checker?

No. PDF Encryption Checker runs entirely in your browser — there is nothing to download, no extension and no desktop program. It works the same on Windows, macOS, Linux, Android and iPhone.

Is it safe to use the PDF Encryption Checker online?

Safer than the usual alternative, yes. Most online tools upload your file to a server you know nothing about, where it sits until someone deletes it. Here the file never leaves your device — the processing happens in the page itself, so there is no server copy to leak, retain or sell.

Does PDF Encryption Checker change my file?

The inspection tools only read the file and report what they find, so your document is untouched. Tools that split, merge or compress give you a new file and leave the original as it was.

What is PDF/A and do I need it?

PDF/A is a version of PDF made for keeping documents readable for many years. Some courts, government offices and archives ask for it. If a portal does not mention it, an ordinary PDF is fine.

Can I use PDF Encryption Checker without signing up?

Yes. No account, no email and no fee. Drop in the file and the report or result appears on the page, ready to read or download.

Why was my PDF rejected by a portal?

Common reasons are a file that is too large, the wrong PDF version, a password, missing fonts or pages of the wrong size. Checking those details here usually points to the cause.

Further reading

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