What is passwordless authentication, and why is it not the same as MFA?

Passwordless authentication does without passwords altogether, using biometrics, one-time passwords, magic links, hardware tokens or push messages; MFA, by contrast, combines several factors and one of them may well be a password.

* Passwordless and multi-factor are two independent axes. *

The two are orthogonal: a passkey with biometric confirmation is passwordless and multi-factor; password plus SMS code is MFA but not passwordless.

Go deeper:

• Passwordless authentication (Wikipedia) — magic links, biometrics and FIDO as replacements for the password.
• Multi-factor authentication (Wikipedia) — knowledge, possession and inherence factors and why combining them helps.