Repair PDF

A PDF that won’t open is usually not lost. Most damage happens at the edges: a download that stopped early and cut off the end, an email system that mangled the index that tells readers where everything sits, a missing trailer, or one garbled object in the middle. The pages themselves are often still in the file. Repair PDF finds them and writes a working copy.

It starts with a check of the file’s structure and tells you in plain words what’s wrong: no end-of-file marker, an index pointing to the wrong places, objects cut off. It also spots files that aren’t PDFs at all, such as a web page saved with a .pdf name after a failed download, so you don’t waste time.

The repair works in two stages. First the file is read object by object, without trusting its broken index, and written again; if its page list is broken, every page that can be found is copied into a fresh document. Then any page that still can’t be used is drawn by a second, much more forgiving reader and saved as a picture, with its text laid over invisibly so you can still search and copy it. You see which pages were recovered and how, as thumbnails, with the sizes before and after. Your file is repaired in your browser and never uploaded.

1. Tap “Choose a PDF” and pick the damaged file. The checks list shows what’s wrong with it, beside a large view of the file as a PDF reader sees it now (or a note, if it’s too damaged to show).
2. If some pages may need redrawing, pick a quality: 150 dpi is fine for reading, 300 dpi for printing.
3. Press “Repair PDF”. The report says what each stage did and which pages were recovered.
4. The repaired copy opens in the page view; flip between Before and After to compare. If something still looks wrong, press “Rebuild every page as a picture”.
5. Press “Download repaired PDF”.

• Checks the header, end-of-file marker, index, trailer, objects and pages, and explains each problem.
• Recognises web pages, ZIP files and pictures saved with a .pdf name.
• Ignores a broken or missing index and finds the document’s start by itself.
• Keeps bookmarks, forms and attachments when the page list survived.
• Copies every page it can find into a new document when the page list is broken.
• Redraws pages pdf-lib can’t use with pdf.js, keeping their text searchable.
• Page-by-page result with thumbnails, a “picture” or “check” mark on pages that need a look, and sizes before and after.
• Skips junk data in front of the PDF header.

• Always keep the original. The tool never changes your file; it makes a repaired copy.
• If a PDF came from a download or an email, getting a fresh copy from the source is often the quickest fix. Use this when you can’t.
• Redrawn pages are pictures: the text can be searched and copied, but not edited as text, and the file may get bigger.
• A page whose content was cut off is kept and marked “check”: it shows whatever was left. Nothing can bring back data that isn’t in the file.
• Password-protected PDFs need their password removed first with Unlock PDF, unless the damage stops that too.
• After a repair, Compress PDF can shrink a file that grew from redrawn pages.