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ZIP Viewer

Look inside an archive: every entry with size, compressed size, ratio, date and flags, plus warnings for anything suspicious.

Processed locally in your browser

What is ZIP Viewer?

The viewer reads only the central directory of a ZIP file, which is the index stored at its end, so nothing is decompressed or executed and even large archives open instantly. It works for .zip and for the many formats that are ZIP inside: .jar, .apk, .docx, .xlsx, .pptx, .odt, .epub and more.

You get a table of up to 5,000 entries (name, size, compressed size, ratio, modified date, flags) and totals: number of files and folders, total uncompressed size, overall ratio and encrypted entries. Entries are flagged when they have a path traversal (../), an absolute path, a drive letter, backslashes or an extreme compression ratio, which are typical of malicious or booby-trapped archives.

How does it work?

  1. Drop a .zip or ZIP-based file (.jar, .docx, .apk…) on the drop zone.
  2. Read the totals and the status banner: valid archive or suspicious entries.
  3. Scan the table; the flags column shows folders, encryption and warnings.
  4. If everything looks fine, use Extract ZIP to download individual files.

Common use cases

  • Checking what is inside a download before you extract it.
  • Auditing an archive for path-traversal entries (zip-slip) before unpacking it in a build or server pipeline.
  • Seeing the structure of a .docx, .xlsx or .apk file (its inner XML, media or classes).
  • Estimating the real uncompressed size and compression ratio of an archive.

Examples

Look inside an archive: every entry with size, compressed size, ratio, date and flags, plus warnings for anything suspicious.

Privacy

ZIP Viewer runs entirely in your browser. The text or files you provide are processed on your device and are not uploaded, logged or stored on our servers.

Limitations

Sizes and ratios come from archive headers, which a malicious file can misreport; extraction counts real bytes. Only the ZIP format is read (not RAR, 7z or tar), and file contents are not scanned for malware.

Frequently asked questions

What is a zip-slip / path-traversal entry?

An entry named like ../../etc/passwd. If an unpacker trusts it, the file lands outside the target folder and can overwrite important files. The viewer flags these names.

Why is a very high compression ratio suspicious?

Ratios above 200:1 on files of a megabyte or more are typical of zip bombs, small archives that expand enormously. Some data, like logs, can be legitimately compressible.

Can it open password-protected archives?

It lists their entries and marks them as encrypted, but the contents stay unreadable without the password.

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