TECHNICAL GLOSSARY · STANDARDS DEFINITION · VERIFIED 2026-11-10
AES-256-GCM
Authoritative Definition
Advanced Encryption Standard in Galois/Counter Mode (AES-256-GCM) is an authenticated symmetric cipher providing confidentiality and cryptographic tamper-proofing in a single primitive.
Common Aliases:AES-GCMGalois/Counter Mode
## Authenticated Symmetric Encryption
AES-256-GCM is the modern gold standard for symmetric encryption recommended by NIST (SP 800-38D).
### Dual Protection: Secrecy + Integrity
Unlike unauthenticated encryption modes (such as AES-CBC without HMAC), AES-GCM calculates a 128-bit authentication tag over the ciphertext. If any byte of the encrypted file is modified, tampered with, or corrupted, decryption fails automatically, preventing chosen-ciphertext attacks.
Related Client-Side Privacy Tools
Run the in-browser implementations adhering to AES-256-GCM with zero server uploads.