BYTETOOLS

ZIP File Viewer

List everything inside a ZIP file without extracting it. See each entry's size, compression method, ratio, CRC-32 and modified date instantly.

Drop a .zip file here or click to browseAlso works with .jar, .apk, .docx, .xlsx and .epub — all read locally, never uploaded

Archive contents

Drop a ZIP file above to list everything inside it without extracting anything.

What is the ZIP File Viewer?

The ByteTools ZIP File Viewer shows you what is inside an archive without unpacking a single byte. It finds the End of Central Directory record at the end of the file, then walks the central directory to read each entry's name, compressed and uncompressed size, CRC-32 checksum, compression method and MS-DOS modification date.

  • Reads the central directory only — nothing is decompressed
  • Per-entry size, ratio, CRC-32, method and timestamp
  • Handles ZIP64 archives and UTF-8 file names
  • Flags encrypted entries and folder entries
  • Export the whole listing as CSV
  • 100% client-side — your archive is never uploaded

How to use the ZIP File Viewer

  1. 1

    Drop a .zip file onto the box, or click it to browse — .docx, .xlsx, .jar, .apk and .epub work too.

  2. 2

    Read the summary tiles for the entry count, total sizes and how much space the archive actually saves.

  3. 3

    Scan the table for each entry's compression method, packed size, saved percentage, CRC-32 and modified date.

  4. 4

    Copy the listing as CSV or download it if you need to share or diff the contents.

About the ZIP File Viewer

The ByteTools ZIP File Viewer shows you what is inside an archive without unpacking a single byte. It finds the End of Central Directory record at the end of the file, then walks the central directory to read each entry's name, compressed and uncompressed size, CRC-32 checksum, compression method and MS-DOS modification date.

Because only the directory is read and nothing is decompressed, the listing appears instantly even for very large archives. It also works on the many formats that are secretly ZIP files underneath, including .docx, .xlsx, .pptx, .jar, .apk and .epub, and it flags entries that are password-protected.

Your archive is read 100% locally in your browser and is never uploaded. That makes it safe to inspect a client deliverable, an unknown download or an internal build artefact before deciding whether to open it. Since nothing is extracted, an archive with a suspicious payload inside cannot execute anything — you are only ever reading a table of contents.

Frequently asked questions

Can I see inside a ZIP file without extracting it?

Yes. Every ZIP stores a central directory at the end of the file listing each entry's name, sizes, checksum and timestamp. This tool reads only that directory, so you get the complete contents listing without decompressing anything and without writing a single file to disk.

Why does the tool work on .docx and .apk files?

Those formats are ZIP archives with a different extension and a required internal layout. A .docx holds XML parts, an .apk holds compiled Android resources, and both keep the standard ZIP central directory, so the same parser lists them perfectly.

Can it open password-protected ZIP files?

It can list them but not decrypt them. Standard ZIP encryption protects the file contents while leaving the central directory readable, so you will still see names, sizes and dates, and encrypted entries are marked with a lock. Extracting them requires the password and a real archiver.

Why is one entry larger compressed than uncompressed?

Very small or already-compressed data can grow by a few bytes once deflate adds its own headers. The tool reports that honestly as a negative saving rather than hiding it. Good archivers store such entries uncompressed instead, which shows as the Stored method.

Is my ZIP file uploaded to a server?

No. The file is read directly from your disk by your browser and parsed in JavaScript. Nothing is transmitted, so confidential archives stay entirely on your machine.

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