2FA/MFA Brute Force Probability Calculator

This is a calculator to approximate the likelihood of being able to successfully randomly* guess a Two-Factor Authentication/Multi-Factor Authentication code.

This assumes that the token is reset after a certain number of attempts.

Specify the number of possible combinations of the 2FA/MFA code (e.g., a six-digit code would be 1000000 possibilities)

Determine the number of failed attempts allowed before the 2FA/MFA code automatically changes

Optionally, input the number of overall times you attempt the brute force using the previous parameters (default is set to 1)

Result:

*this calculator assumes that every attempted code is random and not brute forced in ascending order, for example. (independent events, not dependent events)