A 2FA code generator (also called a TOTP generator or online authenticator) turns a secret key into a 6-digit one-time password that changes every 30 seconds. Websites use these codes as a second step after your password, so even if someone steals your password, they cannot log in without the live code.

2FA.ac implements the open TOTP standard (RFC 6238) — the same algorithm used by Google Authenticator, Authy, and Microsoft Authenticator. That means the codes generated here are identical to the ones your phone app would show for the same secret key. It works for Gmail, Instagram, Facebook, Amazon, GitHub, Discord, banking portals, and any other service that supports authenticator apps.

Unlike most online generators, your secret key never leaves your device. The cryptographic calculation (HMAC-SHA1 via the Web Crypto API) runs entirely inside your browser — nothing is uploaded, logged, or stored on our servers. You can verify this yourself: the generator keeps working even if you disconnect from the internet after the page loads.

Frequently Asked Questions

What is a 2FA code generator?

A 2FA code generator creates 6-digit time-based one-time passwords (TOTP) from a secret key. These codes refresh every 30 seconds and are used as a second layer of security when logging into websites and apps — the same codes apps like Google Authenticator produce.

Is it safe to enter my secret key on 2FA.ac?

Yes. The entire TOTP calculation runs locally in your browser using the Web Crypto API. Your secret key is never sent to our servers, never logged, and never stored — unless you choose to save it, in which case it stays only in your own browser's local storage.

Can I use this instead of Google Authenticator?

Yes. 2FA.ac uses the same open TOTP standard (RFC 6238) as Google Authenticator, Authy, and Microsoft Authenticator. Enter the same secret key and you will get the same codes. It is handy as a backup when you do not have your phone nearby.

Where do I find my 2FA secret key?

When a website asks you to set up two-factor authentication, it shows a QR code along with a link like 'can't scan the code?' or 'enter key manually'. Clicking that reveals a Base32 secret key (e.g. JBSWY3DPEHPK3PXP). Paste that key here to generate your codes.

Why does my 2FA code change every 30 seconds?

TOTP codes are calculated from your secret key combined with the current time, in 30-second windows. This means a stolen code becomes useless within seconds, which is exactly what makes time-based 2FA so much safer than passwords alone.

Is 2FA.ac really free?

Yes — every tool on 2FA.ac is completely free with no account, no signup, and no hidden limits. The site is supported by non-intrusive ads.