Password Entropy Calculator
Dive deep into the mathematics of password security.
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What is Password Entropy?
Password entropy is a measurement of how unpredictable a password is. It is measured in bits. The formula is E = L × log₂(N), where:
- L is the length of the password.
- N is the size of the character pool (e.g., 26 for just lowercase letters, 62 for alphanumeric).
Every single bit of entropy doubles the difficulty of guessing the password. A 60-bit password is 1 billion times harder to crack than a 30-bit one.
Frequently Asked Questions
Is this password generator safe?
Yes, absolutely. The passwords are generated locally in your browser using your device's cryptographic libraries. Nothing is ever sent to our servers, ensuring your data remains private and secure.
What makes a password strong?
A strong password is long (at least 12-16 characters), complex (mix of uppercase, lowercase, numbers, and symbols), and unpredictable. Avoiding common words, personal information, and sequential patterns (like 1234) is crucial.
Should I valid my password with a strength checker?
It is recommended to check the strength of your passwords to ensure they are resistant to modern cracking techniques. Our Strength Checker tool analyzes entropy and estimates cracking time to help you improve your security.
What is a passphrase?
A passphrase is a sequence of random words (e.g., 'CorrectHorseBatteryStaple') that is easy for humans to remember but hard for computers to guess. They are excellent alternatives to complex random strings for passwords you need to type frequently.
How often should I change my passwords?
Modern security guidelines suggest changing passwords only when you suspect a breach. It is more important to use unique, strong passwords for every account and enable Two-Factor Authentication (2FA) where possible.