OTP

An OTP is a password that is valid for only one login or transaction, typically a short numeric code. Because it expires after use, a stolen or intercepted code is useless moments later. OTPs delivered by authenticator apps or hardware tokens are a common second factor in MFA.

• 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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