Lock multiple files inside a password-protected ZIP archive using military-grade AES-256 or legacy ZipCrypto encryption entirely inside your browser. Zero cloud uploads required.
Drag & drop files into the uploader panel or click "Browse Files" to pick documents to encrypt.
Enter your secret passphrase and select AES-256 (strongest) or ZipCrypto (legacy compatibility).
Click "Protect ZIP" to generate the encrypted archive in browser memory and download your protected .zip.
Client-side ZipWriter creates AES-256 encrypted payload blocks in RAM. Passwords and unencrypted files never reach a network interface.
Protects file contents using robust 256-bit AES encryption headers, rendering data unreadable without the matching passphrase.
Select legacy ZipCrypto when sending files to older operating systems, or AES-256 for modern security requirements.
AES-256 Bit Encryption Standards (WinZip AES Spec): Protecting sensitive zip archives requires strong symmetric encryption. BunchTool implements AES-256 encryption, utilizing 256-bit keys and HMAC-SHA1 authentication tags to protect archive payloads against unauthorized extraction and brute-force inspection.
PBKDF2 Salted Key Derivation & Password Strength: Passwords are stretched using PBKDF2 (Password-Based Key Derivation Function 2) with random 128-bit salts. This computational barrier prevents rainbow table attacks and protects encrypted financial spreadsheets, tax records, and client archives.
100% In-Browser Encryption Privacy: Password generation, key derivation, and payload encryption execute 100% locally in web browser RAM using WebAssembly crypto primitives. Encryption passwords and un-encrypted files are never uploaded to remote server storage.