Recover a Corrupt Zip File - Options

Last reviewed 2026-04-27. Browser tools can extract recoverable parts of a damaged zip; full repair usually needs a desktop tool.

Step 1 - re-download

Most "corrupt zip" reports come from a truncated download. The browser stopped the transfer early, or a CDN served a partial file. Fixes that work in seconds before any repair tool: clear the browser cache and re-download; pull the file with a different tool (curl on desktop, a download manager on mobile); or ask for a fresh link if the original came from a chat app where attachment URLs expire.

The diagnostic: run a checksum on the downloaded zip and compare with the sender's. If they differ, the file is the problem, not the zip itself.

Step 2 - partial extract

A zip's central directory sits at the end of the file. If the corruption is at the end, every file inside is unreachable - even though the bytes are still there. If the corruption is in the middle, files before the damaged area still extract.

Try unzip a file in the browser. If it lists contents but errors when extracting, the central directory is intact and one or more file entries are damaged. Some unzip tools (7-Zip on Windows, The Unarchiver on macOS) can extract everything before the damage and skip the rest. Worth trying when only a subset of the files matter.

Step 3 - desktop repair tools

When partial extract fails, repair tools can rebuild the central directory by scanning for file headers in the body. Two free options:

• 7-Zip on Windows. Right-click the corrupt zip, choose 7-Zip > Open. If it can scan the body, it lists what it finds - even with no central directory.
• zip on Linux/macOS. The command zip -FF broken.zip --out fixed.zip attempts to fix a zip with damaged structure. Works for many cases where the file ends mid-entry.

Browser-based repair is rare because the algorithms scan large files and run faster on local disk. If you do not have a desktop available, the right path is usually to ask the sender to resend.

Step 4 - when to give up

If the zip was created with encryption and the corruption is anywhere near the file headers, the contents are likely unrecoverable. Same if the storage media (a failing USB drive, a damaged SD card) was the source - the corruption is in the bytes themselves, not the wrapping. The right move is to ask the original sender to resend, or to restore from a backup if one exists.

Prevention going forward

For files that matter, send a checksum alongside the zip. The recipient can verify the download is byte-perfect before they spend time on a repair. MD5 or SHA-256 both work; SHA-256 is the safer pick. See why MD5 cannot be decrypted for the security context. For everything zip-related, see the zip tools hub.