Password Protect ZIP Files in 7-Zip

Yes, 7-Zip fully supports password protection when generating standard ZIP files. Users can apply password security using either legacy ZipCrypto or modern AES-256 encryption. This article covers how 7-Zip handles ZIP file encryption, provides step-by-step instructions to password-protect your archives, and outlines the security differences between standard ZIP and 7z formats.

Supported Encryption Algorithms for ZIP

When creating a standard .zip file in 7-Zip, you can choose between two encryption methods:

  • AES-256: A robust, industry-standard symmetric encryption algorithm. It provides strong security against brute-force attacks and is supported by most modern compression tools, including Windows 11's native file explorer and third-party extractors.
  • ZipCrypto: A legacy encryption algorithm designed for backwards compatibility with older operating systems and tools (such as older versions of Windows). ZipCrypto has known cryptographic vulnerabilities and should only be used if strict compatibility with legacy systems is required.

How to Create a Password-Protected ZIP File

  1. Select the files or folders you want to compress.
  2. Right-click the selection, hover over 7-Zip, and select Add to archive....
  3. In the dialog box, set the Archive format dropdown to zip.
  4. In the Encryption section on the right:
    • Enter your desired password in the Enter password field.
    • Re-enter the password in the Reenter password field.
    • Select AES-256 (recommended) or ZipCrypto from the Encryption method dropdown.
  5. Click OK to generate the encrypted ZIP file.

Limitation: Encrypting File Names

While 7-Zip can password-protect the contents of a standard ZIP file, the standard ZIP specification does not support filename encryption. Anyone who opens the .zip archive can view the list of files, extensions, and file sizes inside, though they cannot view or extract the actual file data without the password.

If you need to hide the file names and folder structures entirely, select 7z as the archive format instead of zip, which enables the Encrypt file names option.