Run a repair with no settings
The page shows no option fields for this tool. The Options card lists the output format, PDF, and has no field to fill in, so the whole job is the file plus one instruction: repair.
Repair PDF
or drop a file anywhere here
Dropbox
Google Drive
Files other than PDF are converted first. Signing in raises the size limit.
Or start from a blank IRS form
Browse all IRS forms →- You add
- One damaged PDF
- You set
- Nothing, it runs as it is
- You get
- A repaired PDF, or an error
A PDF can be damaged by an interrupted download, a failed copy or a program that closed while saving, and a viewer may then refuse to open it. Repair PDF gives such a file another chance. You add the PDF and run the job, and indox sends the file to the repair function of its PDF engine with no settings attached. When the engine succeeds, you download a new PDF. When it cannot repair the file, the job fails with an error, and indox does not return the damaged upload in place of a result. The tool does not promise a recovery, and it does not list what it fixed.
What can you do when you repair a PDF?
Get a clear outcome
A job ends in one of two ways. Either the result card offers a Download button, or the error card appears with a Try another button. A failed repair does not fall back to handing your upload back.
Keep the damaged original
The job works on the uploaded copy, and the file on your device is not changed. Keep it, because a second attempt with other software needs the same starting point.
Check the file before you rely on it
indox does not open the repaired PDF to count pages or compare it with the original. After the download, page through the document and confirm that the text, images and page count are what you expect.
What repair keeps and what it changes
Stays the same
- Every page the engine can still read, in the same order.
- The file on your device. The repair works on the uploaded copy and you download a new file.
- The output format. A successful repair gives you a PDF.
Changes
- The file is written out again as a new PDF. The engine tries Ghostscript first, then qpdf, then a plain load and save, depending on which of them its install has.
- A Ghostscript rewrite may drop parts that do not mark the page. Its documentation names hyperlinks, bookmarks and comments, and says Link and Widget annotations are not preserved by default.
- The qpdf fallback rewrites the file in a readable form with object streams switched off, so the result can be larger than the original.
- The page does not list what was wrong or what was fixed, so open the result and check it.
How to repair a PDF in 3 steps
Add the damaged PDF
Drop the file on the upload box, or press Choose file and browse to it. The file card shows its name and size.
Start the repair
There is nothing to configure. Press Run Repair PDF and wait while the progress bar moves.
Download and inspect the result
If the repair worked, choose Download and open the new PDF in your viewer. If the error card appears, the file could not be repaired here.
Why repair a PDF with indox?
This page is direct about what a repair can and cannot do. There is one button, no settings to guess at, and two possible endings that you can tell apart. A repair that fails is reported as a failure, and indox does not pass the damaged upload back to you as a finished result. The tool is listed as free in the catalog, and a single repair runs without an account. Your PDF travels to indox over HTTPS, and files uploaded on the free tier are deleted automatically within 24 hours after the job finishes.
- No settings to learn
- Success and failure shown as separate cards
- No silent return of the damaged upload
- One repair without an account
- Free-tier uploads deleted within 24 hours of the job
What are the limits when you repair a PDF?
- Size
- The free tier has a file size limit. Signing in raises it, and paid plans raise it further.
- Formats
- This tool works on PDF files. To change a file's type, use the PDF converter.
- Privacy
- Files are encrypted in transit and processed on indox infrastructure.
- Deletion
- Free-tier files are deleted automatically within 24 hours after the job finishes. Signed-in output stays in your history for your plan's retention period.
Limits worth knowing
- A repair is not guaranteed. If the engine cannot repair the file, the job fails and you download nothing.
- The file has to begin with the PDF signature. A file that lost its opening bytes, or that was never a PDF, is turned away.
- indox does not tell you how much of the document came back. Pages, images or fonts that were lost in the damage may still be missing from the result.
- The tool works on a damaged file, not on its content. It does not correct typos, sharpen a blurry scan or restore pages that were never saved.
- The page has no field for a password. If a protected file still opens with its password, run Unlock PDF on it first.
When the result is not what you expected
| What you see | Why | What to do |
|---|---|---|
| The repaired file opens but links or bookmarks are gone | The file was rewritten, and a rewrite can leave out parts that do not mark the page | Compare with the original. If you need the bookmarks back, rebuild them with Edit TOC. |
| The job fails and nothing downloads | The engine could not repair the file with the tools it has | Try again once. If it fails again, open the original in another viewer or export it again from the program that made it. |
| The file is rejected as not a PDF | The file does not start with the PDF signature | Check the file type and the download. A file cut off at the start cannot be repaired here. |
| The file asks for a password | The page has no field for one | Remove it with Unlock PDF, then repair the open copy. |
| The repaired file is much larger | The qpdf fallback writes a readable form of the file | Shrink it with Compress PDF. |
What do the free and paid plans add?
Free
- All converters
- Daily credit refresh
- Email support
Basic
- Access to all features
- AI Extract
- Priority conversions
- Email support
Highest priority
Premium
- Everything in Basic
- Highest priority queue
- Larger file limits
- Priority support
Pay-As-You-Go
- No subscription
- Credits never expire
- Opt-in auto-refill
- Access to all features
What else can you do with a PDF?
Who repairs PDFs?
People with an interrupted download
A PDF from a portal or an email stopped partway and now shows an error in the viewer. Try a repair before you ask the sender for the file again.
Anyone recovering files from old storage
Documents copied from an aging drive or memory card sometimes will not open. Run each one through the tool and keep the ones that come back readable.
Staff processing documents in bulk
One file in a batch stops a later step, such as a conversion. Repair that single PDF, check it, then feed it back into the batch.
When to try a repair, and when to pick another tool
- A viewer says the PDF is damaged or cannot be opened.
- Another indox tool fails on a file that looks like a normal PDF.
- A PDF opens, but your viewer warns that it had to fix errors while reading it.
- The file asks for a password. That is protection, not damage, and Unlock PDF is the tool for it.
- The pages are there but the scan is hard to read. A repair is not an image fix, so try Adjust Contrast or OCR PDF.
Where can I read more?
Sources
- RepairController source, v2.14.2Stirling-PDF on GitHub
- Vector devices: pdfwriteGhostscript documentation
- qpdf manual: command-line optionsqpdf project
Facts checked on October 16, 2026
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Repair PDF FAQs
What happens if my PDF cannot be repaired?
The job fails. The page shows the error card with a message and a Try another button, and there is no file to download. Your original is still on your device, unchanged.
Does Repair PDF recover every page?
It cannot promise that. The tool returns whatever the repair function was able to write, and indox does not compare it with the original. Count the pages yourself after the download.
Are there any settings?
No. The one choice on the Options card is the output format, and PDF is its single value. The job starts as soon as you press Run Repair PDF.
Why was my file rejected as not a PDF?
indox checks the opening bytes of the upload for the PDF signature before it starts. A file that fails this check is not passed to the repair function, even if its name ends in .pdf.
Can it repair a password-protected PDF?
The page cannot take a password. If the file opens with its password elsewhere, remove the protection with Unlock PDF and repair the unlocked copy.
Will the repaired file look the same as the original?
This page makes no claim either way. It shows no preview and no comparison, so open the result and look through it.
Do I need an account to repair a PDF?
No. Repair PDF is a free tool in the catalog and one job runs without signing in. The free tier has a file size limit, which signing in raises.
Is my damaged file kept?
The upload is sent over HTTPS when you press Run Repair PDF. On the free tier, indox deletes the uploaded file and the result automatically within 24 hours after the job ends.