Repair a PDF file that shows an error instead of pages
You tap the file and get a grey screen. Or a message: the file is damaged and could not be repaired. Failed to load PDF document. Not a supported file type. It is usually the one file you need today, such as an admit card, a signed offer letter or an invoice the client is waiting for.
What is repair PDF, exactly? It helps to know why a PDF goes corrupt. A PDF is not a simple picture of pages. It is a set of numbered parts, such as text, fonts and images, plus an index at the end that tells the reader where each part starts. When the index is broken or missing, the reader gives up, even though most of the content is still sitting there. A repair PDF tool reads the file the hard way, finds the parts and writes a fresh, healthy file around them.
This one is free, runs online, needs no sign-up and puts no watermark on the result. It is also honest: success is not guaranteed, and the next sections explain when it works and when nothing can.
How PDF files get corrupted
Knowing the cause tells you how likely a fix is, and often points to a quicker way out.
- The download was cut short. The network dropped or the tab was closed early, and the end of the file, where the index lives, never arrived. This is the most common case and the most fixable.
- A pen drive or memory card was pulled out while the file was being copied.
- An email system or chat app mangled the attachment on the way.
- The program that made the PDF crashed while saving.
- The storage itself is failing: an old hard disk or a worn-out SD card.
- It is not a PDF at all. A photo or a web page was renamed to .pdf, and no repair can change that.
Three ways we try to fix a corrupted PDF file
When you click Repair PDF, the server works through three methods and stops at the first one that produces a file that opens.
1. Rebuild the index
The index is called the cross-reference table. We scan the whole file, note where every part really sits and write a new table. This fixes most truncated downloads and broken xref errors, and the repaired document is normally identical to the original, with text, links and bookmarks intact.
2. Re-write the file with a second engine
If the first attempt fails, a different PDF engine, one that is more forgiving of odd structure, reads the file and saves it again from scratch. Different engines tolerate different mistakes, so this catches files the first method can't.
3. Salvage the pages
As a last resort we pull out every page that can still be read and build a new PDF from those. You may get 18 pages of 20, or a page with a missing image. For a bank statement or a set of notes, most of the document is far better than none.
Can a corrupted PDF file be fixed every time?
No. Can a damaged PDF file be repaired when the data is physically gone? It can't. A file that shows 0 bytes, or one that was overwritten by other data, has nothing left inside to rescue. Repair works when the content is still there but the structure around it is broken. If we can't produce a file that opens, we tell you so plainly. We never hand back a blank file and call it fixed.
Before you repair: quick checks that often solve it
Half the time the file itself is fine, or a good copy is one tap away. Try these first.
Is it the file or the viewer?
Open the file in something else: drag it into Chrome or Edge on a computer, or use a different reader app on the phone. If it opens there, you don't need to repair the PDF; the viewer was the problem. The same is true of the PDF preview handler error that Windows Explorer and Outlook sometimes show. That is a Windows setting that needs a repair, not your document, so open the PDF directly with a double click.
Get a fresh copy
Look at the file size. A 2 MB report that shows as 40 KB was cut off during download, so download it again on a steadier connection. To recover a PDF from WhatsApp, open the chat and tap the document again so it downloads afresh. If it says the file is no longer available, ask the sender to send it again as a document. On email, download the attachment again instead of opening an old broken copy.
Repair the PDF preview pane on Windows 11
If PDFs open fine but the preview pane in File Explorer or Outlook stays blank, the document is not damaged. To repair the PDF preview pane on Windows 11, open the Settings app, go to Apps, then Default apps, and set a PDF reader that offers previews as the default for .pdf. Then, in File Explorer, open View, Show, and tick Preview pane. The same steps fix the preview handler error on Windows 10. None of this changes your file, so there is nothing to upload here.
Fix corrupted PDF files on Windows 10, Mac, Android or iPad
There is no repair PDF app or desktop program to install. The page works in the browser you already have, which helps when the broken file is on a phone and you have no computer nearby.
- Windows: wondering how to fix corrupted PDF files on Windows 10 or 11? Open this page in any browser, select the file from its folder and click Repair PDF.
- Mac: how to fix a corrupted PDF file on a Mac? Follow the same steps in Safari. If Preview refuses the file, the repaired copy usually opens in it.
- Android: here is how to fix corrupted PDF files on Android. Open the site in Chrome, tap Select PDF file, choose the document from Downloads or your WhatsApp Documents folder, then save the result.
- iPad and iPhone: to see how to fix a corrupted PDF on iPad, open the site in Safari and pick the file from the Files app. The fixed PDF saves back to Files.
Can I repair a PDF offline?
Not with this tool. The recovery engines run on our server, so you need a connection to upload the file. If you must repair a PDF offline, try opening the file in a desktop PDF reader and saving it under a new name, or printing it to a new PDF. That sometimes works for mild damage. For anything worse, the three methods here go further.
After the repair: check, then carry on
After you repair a PDF document online, open it and scroll through all of it. Compare the page count with what you expected. Look at tables and images, and try selecting some text. If pages were salvaged, the file may have lost its bookmarks, form fields or a digital signature.
Then finish what you set out to do. If a few pages came back blank or doubled, delete those pages. If you recovered two halves from two damaged copies, merge the PDFs into one. If the fixed file is too big for a portal, compress the PDF. If the text came back as images only, run OCR to make it searchable again, and to change the wording, convert the PDF to Word.
Recover a PDF online free: what recovery means and what it doesn't
People type "recover" and "repair" for the same problem. So, what is recovery for a PDF? On this page it means one thing: taking a file that exists but won't open, and rebuilding it into a file that does. That is what you get when you recover a corrupted PDF online here. It does not mean pulling a deleted file back from a disk, and it does not mean undoing edits.
Recover a corrupted PDF online, free of charge
To recover a PDF file online, select it and click Repair PDF. The same three methods run, in the same order, and it is free: no page limit, no watermark and no queue you can pay to skip. If the pages come back, they come back at full quality, because the content is copied out of the damaged file rather than re-compressed.
Restore a PDF to a previous version
This tool cannot restore a PDF to a previous version, because a PDF does not keep its own history. Once a file is saved over, the earlier content is gone from that file. Look elsewhere instead. Cloud drives keep old versions for 30 days or more: right-click the file in Google Drive, OneDrive or Dropbox and open Version history. Windows File History and Mac Time Machine do the same for local folders, if they were turned on. And the email or chat message the PDF arrived in still holds the untouched original.
Recover a PDF closed without saving
If you filled a form or typed comments and closed the reader without saving, the repair page cannot help either. Nothing was written to disk, so there is no damaged file to fix. Some desktop readers keep an autosave copy and offer it when you open the program again, so try that first. Otherwise the fastest route is to open the original PDF and redo the work.
Fix a broken PDF online or install a PDF repair application?
A PDF repair application for Windows or Mac does roughly what this page does: it scans the file for objects and writes a new structure around them. The difference is where the work happens and what you have to install. To fix a broken PDF online you need a browser and a few seconds; a desktop program needs a download, a licence check and often a payment before it will save the result. Try the free route first. If it fails, a paid tool is unlikely to do better, because both are limited by what survives inside the file.
Do you need a PDF recovery app on your phone?
No. A PDF recovery app from the app store usually wraps the same kind of engine in a paywall and asks for storage permissions it does not need. On Android or iPhone, open this page, select the file and download the result. It takes less time than the install would.
Repair a PDF for printing
Some files open on screen but refuse to print, or print blank sheets, or stop halfway with a spooler error. That is usually a broken font or image object that the printer driver cannot handle, while the viewer quietly skips it. Run the file through the repair to rewrite it cleanly and try printing again. If it still fails, convert the pages to JPG at 216 or 300 dpi and print those, or make a new PDF from the images. You lose selectable text but you get your printout.