Aegis vs 2FAS: The Best Open Source Authenticators Compared

Why People Choose Open Source Authenticators

The big tech authenticators work fine for most people, so the open source crowd is specifically opting into something else: auditable code, no account requirement, and real export freedom rather than a vendor holding the keys to your backup. Both Aegis and 2FAS deliver all three of those, both are free with zero upsells or ads anywhere in the interface, and both implement the exact same standard TOTP as every commercial competitor, meaning identical secrets produce identical codes, provable with our own browser generator. The choice between them genuinely comes down to platform availability and personality, not security.

The Comparison

The Case for Aegis (Android Power Users)

• The vault model. Your entries live in a genuinely encrypted database, locked behind a password or biometrics, exportable as a single encrypted file you back up wherever you personally like: Syncthing, an external drive, your own NAS. Nothing ever leaves the device unless you deliberately move it yourself.
• Import superpowers. Aegis reads exports, and in many cases even raw app backups, from a genuinely long list of other authenticator apps, which is why it is often the app people land on specifically when consolidating years of scattered 2FA accumulated across multiple old apps.
• Power features. Bulk editing across many entries at once, custom icons per entry with several community icon packs available, entry search, HOTP support for the handful of services that still use counter-based codes instead of time-based ones, and Steam entry support, meaning it can hold Steam Guard codes directly (the format background is in our Steam Guard piece).

The one real line against it: Android only, with no iOS build in development or planned. An iPhone anywhere in the family means a split setup across two different apps, which is exactly the gap 2FAS exists to fill.

The Case for 2FAS (Cross-Platform Friendliness)

• Both platforms, one consistent experience. iOS and Android apps of genuinely equal quality, with encrypted cloud backup riding on whichever cloud account you already use, iCloud or Google Drive, which is the practical answer for mixed-device households rather than asking everyone to standardize on one phone brand.
• The browser extension. A genuinely clever flow: the browser extension requests a code, your phone shows an approval prompt, you tap once, the code fills automatically on the desktop. Real desktop convenience without ever putting the actual secret on the desktop machine.
• A gentler learning curve. Setup and daily use both feel consumer grade rather than developer grade: this is the open source app you can hand to a relative and recommend without expecting a support call afterward.

Privacy-Maximalist Versus Convenience-Leaning: Which Actually Fits You

If your instinct is that any cloud involvement at all, even fully encrypted cloud involvement you cannot read the contents of, is an unnecessary attack surface you would rather not have, Aegis on Android with manual export to storage you personally control is the more disciplined choice, and it rewards that discipline with import compatibility that makes consolidating other apps' exports painless. If your instinct is that a properly end to end encrypted backup riding your existing iCloud or Google account is a perfectly reasonable trade for never worrying about losing your codes when a phone dies unexpectedly, 2FAS is built around exactly that trade and does it well, plus it is the only one of the two that works at all if an iPhone is anywhere in the household. Neither answer is the objectively correct one; they reflect two coherent, defensible positions on the same underlying question.

Decision shortcut: an Android-only tinkerer who wants to own the entire backup pipeline personally should pick Aegis. Anyone with an iPhone in the picture, or anyone who wants encrypted cloud backup without having to think about it further, should pick 2FAS. Nobody loses either way; both are genuinely excellent, audited, free software.

Backup Discipline (Same Lesson, Both Apps)

Open source apps hand you backup responsibility along with backup freedom, and that trade only pays off if you actually act on it:

1. Enable or export the encrypted backup right now, not after the phone breaks: the Aegis vault file copied to two separate locations, or 2FAS cloud backup switched on and confirmed working.
2. Store the backup's own password inside your password manager as its own entry: an encrypted backup file with a forgotten password protecting it is functionally abstract art, beautiful and useless.
3. Keep per-account backup codes regardless of which authenticator app you choose (the full system); app-level backup and account-level backup codes protect against two genuinely different failure modes, not the same one twice.
4. Actually test one restore before you ever need it under pressure: our lost phone playbook describes exactly the drill most people skip until it is too late.

Frequently Asked Questions

How do I migrate from Google Authenticator into either app?

Both import Google Authenticator's built in export QR directly: open the menu, choose Transfer Accounts inside Google Authenticator, then scan that QR with the Aegis or 2FAS import screen. It takes minutes rather than evenings for a large collection of accounts; full details in our transfer guide.

Are these apps actually independently audited, or just "open source" as a marketing claim?

Both have published genuine third party security audits alongside their fully public source code. Open source by itself only enables outside scrutiny, it does not automatically guarantee anyone performed it; these two specifically are among the properly examined open source authenticators, not just publicly readable ones.

Can I run one of these plus Google Authenticator at the same time?

Freely, and with no conflict: scan the same enrollment QR into both apps during setup, or simply keep different accounts split across different apps entirely. Standard TOTP means no single app has any exclusive claim over an account; some genuinely security-conscious people deliberately keep their most important handful of accounts enrolled in two apps at once as built in redundancy.

Which one handles a stolen, not merely lost, phone better?

Both lock behind biometrics or a PIN with the underlying storage encrypted at rest, so a thief faces the phone's own lock screen security plus the app's separate encryption on top of that. The response drill afterward is identical either way: restore your codes onto a replacement device from backup, and rotate anything genuinely sensitive as a precaution; our playbook covers the stolen-phone scenario specifically, not just the lost one.

Do either of these support passkeys?

No, both are dedicated TOTP apps specifically; passkeys instead live in platform keychains and password managers (the full landscape is in our passkey explainer). Running passkeys for whichever accounts support them, and Aegis or 2FAS for the long tail of accounts that only offer TOTP, is a thoroughly modern and entirely sensible setup to run side by side.

Does either app support custom icons or themes for a large account list?

Yes, both let you assign a custom icon per entry so a long list of accounts is scannable at a glance rather than a wall of identical gray placeholders, and both ship light and dark themes. 2FAS additionally auto-matches many common brand icons automatically during setup, while Aegis leans on community-maintained icon packs for the same visual result.