TOTP Generator / Verifier

Generate TOTP shared secret (Base32), compute current code and countdown in real-time, generate otpauth:// URI and QR code (scannable with Google Authenticator / Authy), and verify a code. All computed in-browser; secrets never uploaded.

For development and debugging:

QR Code Import — upload a otpauth:// QR code image (decoded locally with jsQR), or paste otpauth:// URI directly to auto-populate fields.
Save as Bookmark — "add to address bar" encodes current TOTP into URL fragment (#t=…), press Ctrl+D to bookmark, next time the bookmark auto-restores; also copy bookmark link.
Local List — "save to local list" stores multiple TOTPs in browser localStorage, each entry generates codes in real-time, one-click code copy, edit or delete. Great for testing multiple accounts simultaneously.

Security Note

Bookmark links and local lists store plaintext secrets (in URL / bookmarks / localStorage), for test keys only; never store production TOTP secrets.

Integration with Mock

This site's Mock TOTP Verifier computes/verifies codes server-side with the same secret: curl "https://mock.authn.tech/totp/code?secret=<your-secret>"

See HOTP / TOTP Algorithm Details.