Client-Side File Encryptor & Decryptor
Protect confidential documents, spreadsheets, and archives using native browser AES-256-GCM encryption. Zero bytes leave your device.
MultiToolX never stores your password. If you lose this password, the file cannot be recovered.
Upload a file and enter a passphrase to begin client-side encryption.
100% processed locally inside your browser memory.
Zero-Knowledge In-Browser Cryptography
Unlike traditional cloud encryptors that transmit your files across the internet to third-party servers, MultiToolX leverages the hardware-accelerated Web Crypto API built directly into modern web browsers.
Cryptographic Architecture
- Key Derivation: PBKDF2 with SHA-256, 100,000 iterations, and a unique 128-bit cryptographically secure random salt for every file.
- Cipher: AES-256 in Galois/Counter Mode (GCM), providing authenticated encryption that prevents data tampering and chosen-ciphertext attacks.
- No Passwords Stored: MultiToolX does not store, log, or transmit passwords. Only you hold the decryption key.
How to Use Client-Side File Encryptor & Decryptor (Step-by-Step)
Choose 'Encrypt File' or 'Decrypt File' mode.
Select or drop your file into the tool.
Enter a strong secret password.
Click Encrypt or Decrypt and download the secured file.
Applications
Common Use Cases
- Encrypt private PDFs, spreadsheets, photos, and archives before uploading to cloud storage.
- Decrypt previously encrypted .enc files using your secret passphrase.
- Ensure complete data confidentiality with hardware-accelerated Web Crypto.
Privacy Guarantee
Zero Server Uploads
Unlike traditional online converters that upload your confidential documents to external cloud servers, MultiToolX executes computations in your browser runtime via HTML5 Canvas, Web Crypto, and WebAssembly.
Your data never leaves your device and cannot be viewed, stored, or harvested by anyone.
How to Encrypt Files Locally in Your Browser Using AES-256-GCM Web Crypto
A technical walkthrough of browser-based file encryption using Web Crypto API, AES-256-GCM authenticated cipher, and PBKDF2 key derivation.
FAQ
Frequently Asked Questions
What encryption algorithm is used?
Military-grade AES-256-GCM (Galois/Counter Mode) with 100,000 PBKDF2 iterations and unique cryptographically secure 128-bit salts.
Are files uploaded to MultiToolX servers?
Never. 0 bytes leave your machine. Processing happens entirely within your browser runtime using the native Web Crypto API.
Can MultiToolX recover my password if I forget it?
No. MultiToolX adheres to zero-knowledge cryptography. If you lose your password, the encrypted file cannot be decrypted by anyone.
Embed the Client-Side File Encryptor & Decryptor on Your Website or Blog
Enhance your articles and give your visitors a fast, 100% free browser utility with zero installation. Copy our responsive iframe code with one click.