2FA
2FA (noun) means Short for two-factor authentication: a login check that asks for two different kinds of proof of identity, usually a password plus a code from a phone or a physical security key. Example: “Every admin account on the system has 2FA switched on.”
How to Use 2FA
Learner’s notesIn plain EnglishA second check on top of your password when you log in.
Written as 2FA, occasionally 2-FA. Spoken letter by letter after the digit: 'two-eff-ay'. Common in both technical and everyday online writing.
2FA is a noun, not a verb; write 'enable 2FA on the account', not '2FA the account'.
Trace the full origin ↓Fill the Gap
Can you complete this real example?
Every admin account on the system has _____ switched on.
Etymology
An initialism of two-factor authentication.
Synonyms
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Related Words
Rhymes for 2FA
See all rhymes for 2FA →Frequently Asked Questions
Is 2FA the same as a passkey?
No. 2FA adds a second check alongside a password, which still exists and can still be stolen. A passkey removes the password from the process entirely and replaces it with a key stored on a device, unlocked by a fingerprint, face scan or device PIN.
What is the difference between 2FA by text message and 2FA by app?
Both deliver a short code, but a text message travels through the mobile network to a phone number, while an authenticator app generates the code on the device itself from a shared secret. Because a phone number can be moved to a different SIM, the two methods do not carry the same risk.
What is a backup code in 2FA?
A backup code is a one-use string issued when 2FA is set up, meant for the case where the usual second factor is unavailable, such as a lost phone. Each code works once and then stops being valid.