Frequently Asked Questions

Two-factor authentication (2FA) is a security method that requires two separate forms of verification before granting access to an account. Typically this is something you know (your password) plus something you have (a one-time code from an authenticator app or SMS). Even if someone steals your password, they cannot log in without the second factor. Read our full 2FA guide →

TOTP stands for Time-based One-Time Password (RFC 6238). It is a 6-digit code that changes every 30 seconds, computed from your secret key and the current time using HMAC-SHA1. Both your authenticator and the website compute the same code independently, so the server can verify you are who you say you are without the code ever traveling over the network unprotected. Learn more about TOTP →

Your 2FA secret key is a Base32-encoded string (e.g. JBSWY3DPEHPK3PXP) provided by your account's 2FA setup page. It is the shared seed used to compute TOTP codes. You typically scan it as a QR code into an authenticator app, or paste it directly here.

Base32 uses uppercase letters A–Z and digits 2–7. A typical secret looks like: JBSWY3DPEHPK3PXP. It may be 16–64 characters long with spaces or dashes that are just formatting you can ignore.

Yes. Your secret key is processed 100% in your browser using the Web Crypto API. It is never transmitted to our servers. To verify: open DevTools (F12) → Network tab, then generate a code. You will see zero outgoing requests carrying your secret.

No. 2FA Fast stores nothing on our servers. If you use the Save feature, your account labels and secrets are stored in your browser's localStorage, on your device, under your control. Clearing your browser data removes them permanently.

No. Knowing a TOTP code does not grant access to your accounts. You still need your username and password. TOTP codes expire every 30 seconds and cannot be reused. 2FA Fast only generates codes; it has no connection to your accounts.

If your secret key is compromised, regenerate 2FA on your account immediately (disable and re-enable 2FA to get a new secret). A leaked secret key allows anyone who has it to generate valid codes. Treat it like a password.

When setting up 2FA on any website, look for a "manual entry" or "can't scan QR code" option. The site will show you a text secret key you can copy. Alternatively, most authenticator apps let you view the underlying secret of saved accounts.

When you enter a secret key, 2FA Fast generates a URL like https://2fafast.com/2fa/YOURSECRET. Opening this URL on any device instantly shows the live code, no app needed. Use it for personal quick access (e.g. a bookmarked device). Never share this URL publicly, as it contains your secret.

TOTP codes are time-based, so your device clock must be accurate. If codes are rejected: (1) sync your device clock to internet time, (2) make sure you are using the correct secret key, (3) try the code during the first 5 seconds of the 30-second window for best reliability.

Yes. 2FA Fast uses the identical TOTP algorithm (RFC 6238, HMAC-SHA1) as Google Authenticator, Microsoft Authenticator, Authy, and all standard apps. The codes are identical. It is a reliable backup when your phone is unavailable.

Yes. 2FA Fast is fully responsive and works in every modern mobile browser (Chrome, Safari, Firefox, Edge). No app download required.

Beyond the main TOTP generator, 2FA Fast offers 17+ free browser-side tools: QR Code Generator & Decoder, Password Generator, Hash Generator (MD5, SHA-256, SHA-512, HMAC), Text Processor, Base64 & URL Encoder/Decoder, Hex Converter, Password Strength Meter, Basic Auth Generator, Passkey Tester, Percentage Calculator, Cookie Converter, Secure Notepad, and more. See all tools.

The QR Code Generator creates an otpauth:// QR code from your secret key. Scan it with Google Authenticator, Authy, or any TOTP app to add the account without typing the key manually.