One-time password

One-time password definition

One-time password is a user authentication mechanism applying a unique numeric or alphanumeric password that can be used only once.

One-time passwords protect users against password theft and identity theft. The single-use password is created and sent to the user – usually via a text message – to confirm the user's identity.

One-time password examples

One-time passwords are commonly used in services that deal with personal data, such as online banking. They are also popular in corporate networks, allowing employees to log in securely and protecting companies from unauthorized access.

Use of a one-time password

One-time passwords sometimes replace standard ones. In this case, the user gets a unique code for each session and does not have a static password at all.

One-time passwords are often used with 2FA (two-factor authentication) or MFA (multi-factor authentication). The user logs in to a service or network with their login and standard (static) password and then confirms their identity via a single-use code.

Some services generate one-time passwords only if they do not recognize the new device and need to confirm the user's identity.