2FAS Auth

A free, open-source authenticator for iPhone and Android that needs no account and pairs with a browser extension.

Verified facts: 5 of 5
Alternatives ranked: 5
Approved reviews: 0
Visits sent from here: 0

About 2FAS Auth

2FAS Auth is a free, open-source two-factor app from the 2FAS team. It works without an account, email or phone number, generates codes offline, and stores tokens locally, with optional sync and backup through your own iCloud or Google Drive, or via encrypted 2FAS export files. A companion browser extension for Chrome, Firefox, Edge, Brave, Opera and Safari lets you request a code from the browser and approve it on your phone, with traffic end-to-end encrypted, so you do not have to retype codes. The app has icons for many services, groups, search and support for 16 languages, and imports from several other authenticators. The team also makes a separate password manager, 2FAS Pass, and accepts donations. The source code for both the iOS and Android apps is on GitHub under GPL-3.0. There is no standalone desktop app, so the browser extension still depends on your phone being nearby.

Best for: People who want a free, account-free authenticator on both iPhone and Android.

What works

Free, open source and needs no account
Browser extension sends codes from your phone
Backup via your own iCloud or Google Drive
Available on both iOS and Android

Why people leave

No standalone desktop app
Browser extension needs your phone for each code
Cross-platform sync between iOS and Android relies on export files

Top 2FAS Auth alternatives

See all 5

1
Aegis Authenticator
More advanced vault and backup options for Android-only users.
66.5
2
Ente Auth
Adds end-to-end encrypted sync and native desktop and web apps.
62.6
3
Proton Authenticator
Encrypted cross-platform sync plus desktop apps, also free.
59.6
4
Bitwarden Authenticator
Similar free, account-free app from the Bitwarden team.
57.2
5
Google Authenticator
Simpler app with Google Account sync, widely referenced by sites.
55.3

Why people left 2FAS Auth

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2FAS Auth: common questions

Is 2FAS Auth free?

Yes. 2FAS Auth is free, open-source software.

Is 2FAS Auth open source?

Yes. The source code is on GitHub at twofas/2fas-android.

What platforms does 2FAS Auth run on?

2FAS Auth is available for iOS, Android and Browser extension.

What are the best alternatives to 2FAS Auth?

The highest-ranked 2FAS Auth alternatives right now are Aegis Authenticator, Ente Auth and Proton Authenticator. See the full ranked list for pricing, platforms and verified facts.

See all 5 2FAS Auth alternatives

2FAS Auth facts

5 of 5 verified

License: GPL-3.0; Checked Oct 25, 2026github.com(opens source in a new tab); “License: GPL-3.0 (GNU General Public License v3.0).”
Price: Free; Checked Oct 25, 20262fas.com(opens source in a new tab); “It's 100% free and works offline.”
Account required: No; Checked Oct 25, 20262fas.com(opens source in a new tab); “doesn't require an account to use.”
Browser extension: Chrome, Brave, Firefox, Edge, Opera, Safari; Checked Oct 25, 20262fas.com(opens source in a new tab); “Add 2FAS Auth to your web browser by installing our extension for Chrome, Brave, Firefox, Edge, Opera and Safari.”
Sync and backup: Export files, iCloud or Google Drive; Checked Oct 25, 20262fas.com(opens source in a new tab); “Sync between devices Sync between devices Synchronize your Tokens with 2FAS export files, iCloud or Google Drive.”