Your seed phrase backup is probably readable by anyone who finds it. Plain text, plain metal — one bad day and it's gone. SeedVault turns it into an encrypted QR code. Without the password, it's noise. — AES-256-GCM via Web Crypto API — PBKDF2, 600k iterations, random salt + IV — Zero network requests, works fully offline — Single HTML file, zero dependencies — Scan & decrypt with phone camera — Steganography: hide backup inside any image — Metal engraving option Open source. Free forever.