Word or Excel file shows 0 KB

The document or spreadsheet was there yesterday, and now File Explorer says it's 0 KB and it won't open. Here's the honest answer: the file itself can't be repaired, but there's a good chance a copy of your work exists somewhere else.

First, make sure it's really 0 KB

Right-click → Properties and look at Size, not Size on disk. A OneDrive file that's online-only has a size but 0 bytes on disk, and that's normal.
If OneDrive shows a cloud icon or a sync error, let it finish syncing, or open the file from the OneDrive website. The full copy may be safe online.

Why files end up 0 KB

Office saves by writing a fresh file and replacing the old one. If the computer crashes, loses power, or a USB stick or network drive drops out at the wrong moment, you can end up with the new file created but nothing written into it. Sync tools and full disks can do the same. A file that's the right size but all zeros is the same story: space was set aside, but the content never arrived.

Free places to look for your work

Version history. If the file is in OneDrive or SharePoint: right-click → Version history, or use the OneDrive website. Restore the last version with a sensible size.
Previous Versions. Right-click the file (or its folder) → Properties → Previous Versions. This works if File History or restore points were on.
AutoRecover. In Word: File → Info → Manage Document → Recover Unsaved Documents. In Excel: File → Info → Manage Workbook → Recover Unsaved Workbooks. See recovering an unsaved Word document for the folders to check by hand.
Temporary files in the same folder. Show hidden files and look for ~WRL….tmp (Word) or files with random names and no extension (Excel) saved at about the same time. Copy one, rename the copy to .docx or .xlsx, and try opening it. Files starting ~$ are only tiny lock files, not your work.
Other copies. The original on a USB stick or camera card, an email you sent with it attached, a shared Teams or Google Drive copy, or a backup drive.
Undelete software. On a hard drive or USB stick, a free undelete program such as PhotoRec can sometimes find the previous version of the file, because the old content is often still on the drive. Stop using the drive first. On most modern SSDs this rarely works.

Can Office File Repair help?

Not with a 0 KB file, and we'd rather tell you than take your money. There's nothing inside it to recover, and the same goes for a file that's all zeros. If you drop one into Office File Repair it will tell you so, free.

It can help with the copies you find: a temporary file, an older version or a partly saved file that opens with errors. If a copy has some content but Word or Excel calls it corrupt, the free preview shows what's recoverable.

Common questions

Can a 0 KB Word or Excel file be recovered?

Not from the file itself, because it contains no data. Look for another copy: OneDrive version history, Windows Previous Versions, AutoRecover files, temporary files in the same folder, or the copy you emailed or backed up.

Why did my Word document become 0 bytes?

Usually the save was interrupted: the computer crashed or lost power, a USB or network drive disconnected, or a sync tool failed. The new file was created but nothing was written into it.

My OneDrive file shows 0 KB. Is it lost?

Check Size rather than Size on disk in Properties. Online-only OneDrive files use no disk space but still have a size. If it's really 0 bytes, open version history on the OneDrive website and restore an earlier version.

Will file repair software fix a 0 KB file?

No. Repair tools can only work with data that's in the file, and a 0 KB file has none. Be wary of any program that claims otherwise.