Understanding AES-256 in Galois/Counter Mode (GCM)
The Advanced Encryption Standard (AES) with a 256-bit key is the gold standard for symmetric encryption approved by NIST.
In Galois/Counter Mode (GCM), AES provides both confidentiality (scrambling plaintext) and integrity verification (an authentication tag). If an attacker tampers with even a single bit of the encrypted file, decryption fails automatically.
Deriving Keys with PBKDF2 and Cryptographic Salts
Human passwords are too short to serve as raw 256-bit cryptographic keys.
DocSwift utilizes the Web Crypto API's PBKDF2 with HMAC-SHA-256 and 100,000+ iterations combined with a cryptographically random 16-byte salt to resist brute-force and rainbow table attacks.
Step-by-Step Tutorial
Select Document to Encrypt
Drop your PDF or data file into DocSwift Encrypt Tool.
Choose a High-Entropy Password
Enter a strong passphrase or generate one with our Secure Password Generator.
Download Encrypted File
Your browser computes the AES-256-GCM cipher and outputs the encrypted document locally.
Ready to Try It Yourself?
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Frequently Asked Questions
Can DocSwift recover my password if I forget it?
No. Because DocSwift is 100% zero-knowledge, we never store or transmit your password or encryption keys.
Are files encrypted with AES-256 vulnerable to quantum computing?
AES-256 is widely recognized as post-quantum secure against Grover's algorithm, maintaining a 128-bit security margin.