Password Strength
Calculate Password Strength instantly with the exact formula and a worked example.
Password Strength
Password lengthchars
Lowercase letters a–z (1 = yes)
Uppercase letters A–Z (1 = yes)
Digits 0–9 (1 = yes)
Special characters !@#… (1 = yes)
Password strength (1-5)
4
Rating
Strong
Entropy
78.7bits
Character set size
94
Brute-force time (10¹⁰ guesses/s)
754050years
More about: Password Strength
What it calculates
The “Password Strength” calculator computes Password strength (1-5) from 5 parameters: password length (chars), lowercase letters a–z (1 = yes), uppercase letters a–z (1 = yes), digits 0–9 (1 = yes), special characters !@#… (1 = yes).
Standard IT calculations for developers and sysadmins.
Example calculation
With parameters Password length = 12 chars, Lowercase letters a–z (1 = yes) = 1, Uppercase letters A–Z (1 = yes) = 1, Digits 0–9 (1 = yes) = 1, Special characters !@#… (1 = yes) = 1 the result is 4 (Valid only for random passwords; words and patterns are cracked much faster).
How to use
- Enter password length, lowercase letters a–z (1 = yes), uppercase letters a–z (1 = yes), digits 0–9 (1 = yes) and special characters !@#… (1 = yes) — each field above is adjustable with a slider.
- Password strength (1-5) is calculated automatically as you type.
- Check the worked example below to see the formula applied to real numbers.
- Copy the result or bookmark this calculator.
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FAQ
How is Password Strength calculated?
The Password Strength calculator computes Password strength (1-5) from password length, lowercase letters a–z (1 = yes), uppercase letters a–z (1 = yes), digits 0–9 (1 = yes), special characters !@#… (1 = yes). Enter your values above and the exact formula is applied instantly; a worked example with real numbers is shown below.
Is the Password Strength calculator free?
Yes. It is completely free, needs no signup, runs entirely in your browser, and sends no data to any server.
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