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Test a ZIP file

Check every file in a ZIP against its checksum and find out which ones are damaged, on your device. Free, with no account or uploads.

Every file is read in full and checked against the checksum it was saved with.

Drop a ZIP to check it

Or choose one from your computer or phone. For a ZIP cut into parts (.z01, .z02 … .zip), choose every part at once.

  • ZIP
  • RAR
  • 7z
  • TAR
  • tar.gz
  • tar.xz
  • .gz

Stays on your device. No size limit but your device's.

How it works and help

A little help along the way

Follow these steps. Every option is explained underneath. Everything happens in your browser; nothing in the archive is sent anywhere.

  1. Open the archiveDrop it on the page or press Choose a file. For a ZIP cut into parts (.z01, .z02 … .zip, or .001, .002 …), choose every part at once. Nothing is uploaded, and there is no size limit but your device's.
  2. See what is insideThe page says how many files there are and how large they are once taken out. Folders open with a press; Find a file looks through every name. Press the eye beside a file to preview a picture, text, sound or a video.
  3. Type the password, if it has oneLocked files show a padlock. Type the password you were given and press Unlock. It stays on the page and is never kept.
  4. Choose the filesEvery file starts chosen. Untick what you do not want, or tick a folder to choose everything in it.
  5. Take them outIn Chrome and Edge on a computer, Extract into a folder writes the files with their folders into one you choose. In every browser, Download saves one file as it is, or several as one ZIP your device opens by itself. Each row has its own download button too.
  6. Check for damageCheck for damage reads every file in full and compares it with the checksum it was saved with, then names any file that does not match.

Questions people ask

What does the check look at?
Every file is read to its end and compared with the CRC-32 checksum it was saved with, or, for AES-locked files, with their authentication code. The page names each file that does not match and says why.
Can it repair a damaged ZIP?
No. A checksum shows that something changed, not how to put it back. It tells you which files are whole so you can take those out, and you can ask for a fresh copy of the rest.
Why were some files not checked?
Locked files are passed over until you type the password. Files packed with a method the tool cannot open, such as BZip2 or LZMA, are named with the reason, and a check you stop leaves the rest unchecked.
Does it test TAR and .gz files too?
Yes. A .gz file carries a CRC-32 and its length, and both are checked. A tar.gz is read through to its end, so the whole archive is checked, and damage in a TAR's headers is found too.

This page is the Zip and archive tool, opened for this one job; every other tool it has is one press away. Each of its settings is explained on the Zip and archive tool's own page.

Read the step-by-step guide

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