Is my file uploaded to a server?

No. The file is opened by JavaScript and WebAssembly running inside your own browser tab. It is never uploaded, there is no server-side processing and nothing is stored — closing the tab discards everything.

Some pages are still missing.

Then those pages are not in the file. Rebuilding recovers what is present and rewrites the structure around it; bytes that were never received or were overwritten cannot be reconstructed. Getting back most of a document is the realistic outcome for a truncated file.

My PDF opens but behaves oddly. Is this the right tool?

Often yes. A file that opens in one reader and not another, or that prints wrongly, is usually structurally non-conformant rather than damaged. Rewriting it produces a clean file that behaves consistently.

Will anything be lost in the rebuild?

Page content, annotations and structure are carried across. Anything that was already unreadable stays unreadable, and a few exotic features may not survive a rewrite — compare the rebuilt file against what you could see before.

What is the web-view option?

It also linearizes the result, so the first page renders before the whole file has downloaded. Worth turning on if the rebuilt document is going to be published; it makes no difference to a file kept locally.

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Repair PDF

Rebuild a damaged or non-conforming PDF by re-parsing and rewriting it — recovers many files other apps won't open.

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Add a file first.

Drop a PDF here

or click to browse — nothing leaves your device

"The file is damaged and could not be repaired" usually means the reader gave up, not that the document is gone. PDFs break in predictable ways — a truncated download, a cross-reference table that no longer matches the objects, a producer that wrote something not quite to spec — and in most of those cases the pages themselves are intact and merely unreachable. This tool re-parses the file, finds what is actually there, and writes a new, well-formed document around it.

It rebuilds structure; it cannot invent content. If the download stopped halfway then the last pages are genuinely not in the file, and no tool can recover bytes that were never received — expect to get back the part that arrived. Where a reader was simply refusing to open a structurally odd file, the rebuilt version usually opens everywhere.

How it works

Drop in the damaged PDF.
Let it be re-parsed and rewritten.
Optionally also optimize it for fast web view.
Download the rebuilt file and check what came back.

What people use it for

Opening a file that one reader refuses and another shows partially.
Recovering a document from an interrupted download or a failing drive.
Fixing a PDF produced by a system that writes not-quite-conformant files.

Frequently asked questions

Is my file uploaded to a server?: No. The file is opened by JavaScript and WebAssembly running inside your own browser tab. It is never uploaded, there is no server-side processing and nothing is stored — closing the tab discards everything.
Some pages are still missing.: Then those pages are not in the file. Rebuilding recovers what is present and rewrites the structure around it; bytes that were never received or were overwritten cannot be reconstructed. Getting back most of a document is the realistic outcome for a truncated file.
My PDF opens but behaves oddly. Is this the right tool?: Often yes. A file that opens in one reader and not another, or that prints wrongly, is usually structurally non-conformant rather than damaged. Rewriting it produces a clean file that behaves consistently.
Will anything be lost in the rebuild?: Page content, annotations and structure are carried across. Anything that was already unreadable stays unreadable, and a few exotic features may not survive a rewrite — compare the rebuilt file against what you could see before.
What is the web-view option?: It also linearizes the result, so the first page renders before the whole file has downloaded. Worth turning on if the rebuilt document is going to be published; it makes no difference to a file kept locally.

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