2fa-auth.app

What is two-factor authentication (2FA)?

Two-factor authentication (2FA) is a security method that requires two separate proofs of identity before granting access. Even if your password leaks, an attacker still needs a short-lived code, hardware key, or passkey approval to get in. For most apps today, that second factor is a 6-digit authenticator code.

How does TOTP generate one-time passwords?

TOTP (time-based one-time password) is a standard that turns a shared secret and the current time into a short-lived code. When you enable 2FA, the service gives you a secret — usually embedded in an otpauth QR code. Your authenticator combines that secret with the current 30-second window to produce a fresh code each interval.

How to manage multiple 2FA accounts in one authenticator?

You can keep all your TOTP accounts in one place. Add each service with an app name, account label, or short remark, then preview and copy the right code when you need it — no more scrolling through a phone authenticator to find the right entry.

Why store TOTP secrets locally instead of the cloud?

Keeping TOTP secrets on your own device means no server breach can expose them all at once. This tool stores everything in the current browser, making it ideal for personal backup workflows, developer testing, temporary credentials, or separating work accounts from a phone-only authenticator.

How to generate a 2FA code with this TOTP authenticator?

1Paste a Base32 TOTP secret or scan an otpauth QR code.2Add an app name, account, or short remark so the code is easy to recognize.3Copy the current 2FA code before the 30-second timer refreshes.