Check a PDF file
Check whether a PDF has a recognizable file signature, expected end markers, readable document structure, pages, password protection, or a mismatched extension — directly in your browser.
Analyzing your file...
Checking the file structure.
ARADURU is checking this file.
Waiting for the diagnosis.
Wait for the browser-side check to finish.
Building your troubleshooting path.
Waiting for the problem context.
Waiting for the file check.
Waiting for the next step.
WHY ARADURU SAYS THIS
Review file evidence and details
File facts, recovery guidance, and technical checks stay here until you need them.
Show details
Your file at a glance
ARADURU will suggest the safest next action after the file check finishes.
File identity evidence
Technical details View file checks
PDF won't open? Start here.
This checker focuses on common file-side PDF problems. It can help distinguish a readable PDF from a file with a wrong extension, missing end markers, parser failures, or password protection.
What ARADURU checks inside your PDF
The checker does more than look at the .pdf filename. It inspects important PDF markers and uses a browser-side PDF parser to give you a practical diagnosis first.
Does the file look like a real PDF?
Looks for the expected PDF signature near the beginning of the selected file.
Does the PDF end normally?
Checks for the expected end-of-file marker near the end of the document.
Can the document structure be located?
Checks for the cross-reference pointer used to locate important PDF structures.
Can a PDF parser open it?
Uses a browser-side PDF parser to see whether the document structure can be loaded normally.
Are pages detected?
Checks whether the PDF parser can find a readable page tree and report document pages.
Is password protection limiting the check?
Distinguishes a password-protected PDF from a file that simply appears damaged or unreadable.
The result tells you what to do before showing the technical details
You do not need to understand PDF cross-reference tables or parser errors. ARADURU summarizes the practical meaning first and keeps the individual checks inside Technical details.
No obvious PDF structure problem found
The signature, parser, page tree, and expected end markers did not reveal an obvious structural problem.
The PDF needs attention
The file may be readable but have a wrong extension, missing marker, or another structural warning.
ARADURU could only inspect part of the PDF
Password protection or an unavailable browser parser can prevent a complete page-level check.
An important PDF check failed
Keep the original unchanged and obtain a fresh copy before trying repair or recovery on a duplicate.
A healthy structure does not rule out every PDF problem
ARADURU focuses on document structure, markers, parser readability, pages, and protection status. A PDF can still have problems involving fonts, images, forms, annotations, scripts, embedded files, rendering, or viewer-specific behavior outside this structural check.
- Keep the original. Test changes or repair attempts on a copy.
- Try another trusted PDF viewer. A structurally readable PDF can still have viewer-specific issues.
- Get a fresh copy. Re-download or re-request the file if it came from email, cloud storage, or a transfer.
- Do not rename to convert. Changing another file extension to .pdf does not create a valid PDF.
Your selected PDF stays in your browser
The current checker analyzes the selected PDF locally in the browser and does not upload the document to the ARADURU server. The current beta may load JavaScript libraries from a third-party CDN, but the selected PDF is not sent to those library servers by this checker.
Common PDF file-check questions
Can ARADURU repair a damaged PDF?
No. This page diagnoses supported PDF structure and parsing problems and suggests next steps. It does not rewrite or repair the selected document.
Can ARADURU check a password-protected PDF?
Only partially. ARADURU can recognize when a password is required, but this version does not ask for your password or inspect the protected page contents.
Why can a PDF look healthy here but still display incorrectly?
This check focuses on file structure. It does not validate every font, image, form, annotation, script, embedded object, or viewer-specific rendering behavior.
Can it detect a PDF with the wrong extension?
Yes. If the internal file signature and parser indicate PDF content, ARADURU can report that the filename extension does not match.
Does the checker upload my PDF?
No. In the current version, the selected PDF is processed locally in your browser and is not uploaded to the ARADURU server.