Password Strength Checker
Type in a password to check its strength.
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This Password Strength Checker allows you to estimate password strength based on the length and the mixture of characters included in the password. The tool dynamically determines both of those parameters as you input your password, calculates entropy, and provides the overall password strength assessment result.
Entropy is often used to measure password randomness or unpredictability. In simpler terms,, it quantifies how difficult it is to predict a password. The higher the entropy, the stronger the password.
Entropy (H) is calculated using the formula:
Where:
- H is the entropy.
- L is the length of the password.
- N is the size of the character set (e.g., total number of possible characters).
The commonly used character sets with corresponding sizes:
- Numbers (0-9): 10 characters
- Lowercase Latin alphabet letters (a-z): 26 characters
- Uppercase Latin alphabet letters (A-Z): 26 characters
- All ASCII special characters (excluding space): 32 characters
The table below illustrates the entropy associated with passwords of different lengths and based on different character sets:
Password length | |||||
| Character sets | chars / set | 8 | 10 | 12 | 14 |
| Letters (a–z, A–Z) | 52 | 45.6 | 57 | 68.4 | 79.8 |
| Alphanumeric (a–z, A–Z, 0–9) | 62 | 47.6 | 59.5 | 71.4 | 83.3 |
| All ASCII printable characters except space | 94 | 52.4 | 65.5 | 78.6 | 91.7 |
Certainly, password length and character sets play an important role in creation of secure passwords. However, it is also critical to follow the established cybersecurity guidelines and best practices:
- Avoiding Predictability: Do not use easy-to-guess passwords, common words, names, etc.
- Minimizing Repetition: Avoid excessive character or pattern repetitions.
- Use Passphrases: Consider using passphrases - combinations of words or a sequence of words, as a balance between memorability and complexity.
- Use MFA: Enable multi factor authentication if available.