Compare software

Yubico Authenticator vs Proton Authenticator: catalog facts
Yubico Authenticator	Proton Authenticator
Free The app is free; it requires a YubiKey, which is bought separately.	Free Free and open source under the GPL, with no advertising. A Proton account is used for…
Windows, macOS, Linux, Android, iOS	Windows, Linux, Android, iOS
Secrets stay on the hardware key rather than the device Same codes available on any machine where the key is plugged in	End-to-end encrypted sync between devices, which most free authenticators lack Apps for Android, iOS, Windows, Linux and macOS
Requires a YubiKey Losing the key loses access to the stored codes unless you have a backup	Sync requires a Proton account Keeping codes on the same desktop you log in from weakens second-factor separation
Downloadable app	Downloadable app
Closed source	Open source
License not stated	License: GPL-3.0
Not stated if an account is needed	No account needed
Not stated if it works offline	Works offline
Official website Full listing and sources Checked September 24, 2026	Official website Full listing and sources Checked September 21, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.