Repair a Corrupted File
Drop in a damaged file and find out what is actually recoverable — honestly, including when the answer is nothing.
Reading the file…
How to use this tool
- Choose the damaged file. It is read inside this tab — nothing is sent anywhere.
- The whole file is scanned byte by byte for archive headers, ignoring the index that is usually the broken part.
- Each member found is decompressed on its own, so one damaged part cannot take the rest down with it.
- You get a report naming exactly what came back and what did not, a rebuilt file, and where we could read it, the text on its own.
This page handles the family of formats that are ZIP archives underneath: Word, Excel and PowerPoint files, ODF documents, EPUB books, JAR files and plain ZIPs. It detects which one you gave it and applies the right checks. A DOCX, XLSX, PPTX and ZIP are all the same thing underneath: a ZIP archive holding a set of XML files. A ZIP records every member twice — once in a header immediately before the member’s own bytes, and once in an index written at the very end of the file. That index is written last, so an interrupted download or a truncated attachment destroys it first, and it is also the only part most applications read. The contents are still sitting there; the map to them is gone. Recovery means ignoring the map, scanning the raw bytes for every member header, and rebuilding the index from what is actually there. Formats that are not archives — PDF, JPEG, MP4, the old binary Office formats — need different techniques, and this page will tell you so rather than pretending otherwise.
Repair a Corrupted File — the specification
| Handles | DOCX, XLSX, PPTX, ZIP, ODT, ODS, ODP, EPUB, JAR |
|---|---|
| Detects | The real format from the file’s contents, not its extension |
| For PDF | Use the dedicated PDF repair page — a PDF is not an archive |
| Not supported | JPEG, MP4, RAR, 7z, and the old binary .doc, .xls and .ppt |
| Maximum input | 100 MB |
| Uploads | None |
Repair a Corrupted File: what can go wrong
These are the failures that actually come up, in roughly the order they happen:
- The file is a PDF. PDFs are not ZIP archives and need a different repair method entirely.
- The file is a video or a photograph. Those formats are not archives and this will tell you so immediately.
- The file is a .rar or .7z. Different container formats.
- The file is 0 bytes, or no archive headers appear anywhere in it. There is nothing to recover.
How it works
A DOCX, XLSX, PPTX and ZIP are all the same thing underneath: a ZIP archive holding a set of XML files. A ZIP records every member twice — once in a header immediately before the member’s own bytes, and once in an index written at the very end of the file. That index is written last, so an interrupted download or a truncated attachment destroys it first, and it is also the only part most applications read. The contents are still sitting there; the map to them is gone. Recovery means ignoring the map, scanning the raw bytes for every member header, and rebuilding the index from what is actually there.Who needs Repair a Corrupted File
Anyone with a file that will not open and no certainty about why — start here to find out whether it is recoverable at all.
Repair a Corrupted File — frequently asked questions
Which file types does this actually work on?
Anything that is a ZIP archive underneath: .docx, .xlsx, .pptx, .odt, .ods, .odp, .epub, .jar and .zip. That covers most modern document formats. It does not cover PDF, images, video, or the old binary Office formats, and it says so instead of producing a file that looks repaired and is not.
How do I know whether the repair actually worked?
The report tells you. It names every member found, every one recovered, every one lost and why, and whether the specific members an application needs to open the file are present. A partial recovery is labelled as partial.
What cannot be recovered?
Content that is no longer in the file. If a download stopped at 60%, the last 40% is absent and nothing can bring it back. If a disk fault overwrote part of the document with zeroes, that part fails its checksum and is reported as lost rather than quietly returned half-broken. Any tool claiming to fix any corrupted file is describing something that cannot be done.
Is my file uploaded anywhere?
No. The file is read inside your browser tab and the repair runs there. Nothing is transmitted, which is the main reason to use this rather than a service that asks you to upload a damaged work document or dissertation to a server you know nothing about.
Is this tool really free?
Yes. No account, no trial period, no watermark on the output and no cap on how many times you use it. The site is funded by advertising.
Do I need to install anything?
No. There is nothing to download and no extension to add — it runs in the browser you are reading this in.
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Background reading: Free AI and File Tools That Run in Your Browser
Your file never leaves your device. Open your browser's Network tab while you use this page and you will see no upload — how that works.
Disclaimer. Published requirements change without notice. Confirm against the official source before you submit. Full disclaimer.