Password Entropy Calculator
1. Enter Password
Load Sample
2. Password Analysis Details
Entropy Score–
Password Length–
Character Pool Size–
Strength Class–
How to Use the Password Entropy Calculator
- Enter your password into the input field.
- Wait for the tool to analyze the character set.
- View the calculated entropy score in bits.
- Check the strength rating to see if it is secure.
Formulas and Technical Logic
Entropy (E) measures password strength in bits. The formula is E = L * log2(R). Here, L is the password length. R is the pool of possible characters. A standard pool includes lowercase (26), uppercase (26), numbers (10), and symbols (32). A larger pool and longer length create higher entropy.
Key Features
- Real-time entropy calculation.
- Character pool analysis (lowercase, uppercase, numbers, symbols).
- Clear strength rating (Weak, Good, Strong).
- No data saved on servers. Privacy is guaranteed.
Reference Table: Entropy Strength Levels
| Entropy (Bits) | Strength | Cracking Time Estimate |
|---|---|---|
| Less than 40 | Weak | Instant to minutes |
| 40 to 59 | Moderate | Hours to days |
| 60 to 79 | Strong | Years |
| 80 or more | Very Strong | Centuries |
Frequently Asked Questions
What is password entropy?
It is a scientific measure of how unpredictable a password is. It uses bits to show resistance to brute-force attacks.
Is my password saved when I use this tool?
No. All calculations happen in your browser. Your password is never sent to a server.