Every Code That Grants Entry PINs, door codes, one-time passwords, invite codes: AccessCode explains how each works, where each is weak, and how to keep yours out of the wrong hands.

An access code is usually short, often numeric, and tied to a device or door; a password is longer and tied to an account. Short codes rely on lockouts and rate limits to stay safe.

They beat nothing, but SIM-swap and interception attacks make SMS the weakest second factor — authenticator apps or hardware keys are stronger where offered.

Whenever someone with the code no longer needs access, after any suspected exposure, and on a routine schedule for rentals — many hosts rotate per guest.