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Repair PDF
Recover a damaged or corrupt file. Free, no sign-up.
or drop it here
Repair PDF runs inside your browser — your file never reaches our servers.
How to repair a damaged PDF
Repair reads what it can from a damaged file and rebuilds a clean document around the pages it recovers.
- Select the damaged PDF. Even one that other readers refuse to open.
- Repair. The file is parsed tolerantly and its pages copied into a fresh document.
- Download. You are told how many pages were recovered.
What "repair" actually rebuilds
The damaged file is parsed in a forgiving mode: objects that will not parse are skipped instead of throwing, the file is read from the top so objects are found where they actually lie rather than where a broken cross-reference table claims they are, and if the trailer's pointer to the document catalogue is bad the parser goes looking for a valid one. Every page it can still find is copied into a brand-new document, which is written out with compressed object streams. The corrupt structure is not patched; it is abandoned, and a clean one is built around the content that survived.
A page brings its content, its resources and the annotations attached to it. What does not travel is anything held at document level: the bookmark outline, the form dictionary — a filled form usually still shows its values, since those are drawn into the page's own appearance, but the fields stop being editable — and the document properties such as title and author. The repaired file is genuinely a new file. The recovered page count is reported so you can check it against what the document should contain.
When repair is the wrong tool
If the download or transfer stopped early, the missing bytes are gone and nothing can invent them. That case shows up as no readable pages at all, often alongside a file conspicuously smaller than it should be, and fetching the original again is the only fix. A file that was never a PDF — an HTML error page saved under a .pdf name is the classic — has no PDF header at all, so it stops with a parse error before any page is looked for.
Encryption is the other case. Repair opens a password-protected file rather than refusing it, but it never decrypts one, so the page contents are copied across still scrambled and the result is unusable. Run Unlock PDF with the password first, then repair the decrypted copy. If the pages come back intact but the form went with the structure, the Design mode of PDF forms can put fields back over the recovered pages; and a page that displays but will not print is often cured by rebuilding it as an image with Flatten PDF.
Questions
Can every PDF be repaired?
No, and it is worth being honest about that. Repair fixes structural damage — broken cross-reference tables, bad object offsets — which is the common case. If the file was truncated mid-download, the missing bytes are simply gone and no tool can invent them. Try re-downloading the original first.
Will I lose anything?
Possibly. Rebuilding keeps page content but may drop damaged annotations, form data or bookmarks. You are told the recovered page count so you can check nothing is missing.
It says no readable pages could be recovered. Is there anything left to try?
That message means not one intact page could be found, which nearly always means the file is truncated rather than corrupt — the bytes simply stop partway. Download the original again, or ask the sender to re-send it, and compare the file size against the source.
Will repairing change how the document looks?
No. Nothing is re-rendered or re-compressed; the pages are copied as they are and only the file's structure is rewritten. Text stays selectable and images keep their resolution. What can change is behaviour rather than appearance — bookmarks and interactive form fields do not survive the rebuild.
My PDF opens, but a reader complains about an error every time. Is repair worth running?
Usually yes, and it costs nothing to try. Complaints of that kind normally come from a damaged cross-reference table or stray objects, which is exactly what a rebuild discards. Check the recovered page count before you replace the original.
Are my files uploaded to a server?
No. Every tool on this site runs inside your browser, using the same engine as the Folia desktop app. Your file is read from your disk into your browser’s memory, processed there, and handed back as a download. It never crosses the internet, so there is nothing for us to store, leak or hand over.
Is there a file size limit?
We impose none. The only ceiling is your own device’s memory, which differs from one computer to another — so we read what your browser reports about this machine and show the resulting limit on the page. Light tools like merge and rotate handle far more than heavy ones like OCR, which must render every page. For anything larger, Folia for Desktop has no limit at all.
Is it really free? Do I need an account?
Yes, and no. Every tool is free and unlimited, with no watermark and no sign-up. Ads pay for the site, and your own computer does the work, which costs us nothing. Signing in with a paid Folia plan simply removes the ads.