TOTP

TOTP generates short-lived codes by combining a shared secret with the current time, usually in 30-second windows. It is the algorithm behind most authenticator apps like Google Authenticator. Because codes expire quickly and never repeat, they are far stronger than static passwords, though they can still be phished in real time.

• Proton Pass → Open-source password manager from the Proton team with a built-in TOTP authenticator and email aliases. Storing codes beside passwords trades some separation of factors for convenience; know that tradeoff.

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