Password Entropy Calculator
Enter password length and character set size to estimate theoretical entropy. Higher entropy means a stronger, harder-to-guess password.
Entropy is theoretical; follow best practices for secure passwords.
Examples
- 8 characters with a 62-character set ⇒ 47.60 bits
- 12 characters with a 96-character set ⇒ 79.61 bits
FAQ
What is character set size?
It is the number of possible characters for each position in the password.
Does higher entropy mean a stronger password?
Yes. More entropy indicates a password that is harder to brute-force.
Do common words reduce entropy?
Yes. Predictable patterns or dictionary words lower real-world security.
Should length be an integer?
Password length is measured in whole characters, so it should be an integer.
Additional Information
- Entropy increases with both password length and the variety of characters used.
- Real passwords that include words or patterns often have lower effective entropy.