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What does this tool show?
The password generator creates a strong random password from the length and character sets you choose, reports its entropy in bits and a strength rating, and runs entirely in your browser using cryptographic randomness.
Why password length and variety matter
Password strength depends mainly on length and the size of the character pool. Each added character multiplies the number of possible passwords, and each added character set enlarges the pool. A long password from many sets has far more entropy than a short one from a single set, which is why the entropy figure is a better guide than a vague strength label.
Using a password manager
The strongest practice is to use a unique, random password for every account and let a password manager generate and store them. Reusing a strong password across sites is a single point of failure — if one site leaks, every account sharing that password is at risk. This generator's output can be pasted straight into your password manager.
How to judge password strength
Entropy measures the difficulty of guessing a password in the worst case. Roughly: below 40 bits is weak, 40–60 fair, 60–80 strong, and above 80 very strong. Real-world security also depends on not reusing passwords and enabling two-factor authentication wherever possible.
How this calculator works
Formula
A password is generated by randomly picking characters from the selected character sets, guaranteeing at least one character from each set, then shuffling. Entropy = length × log₂(pool size), a measure of how many guesses are needed in the worst case.
Worked example
A 16-character password drawn from lowercase, uppercase, digits, and symbols (a pool of about 78 characters) has roughly 100 bits of entropy — far stronger than a short or common password.
Assumptions to verify
- Generation uses the browser's cryptographically secure random number generator when available.
- Each selected character set contributes at least one character, so enabling more sets raises complexity.
- The password is generated locally and never transmitted.
Frequently asked questions
What is a strong password?
A strong password is long and drawn from a large set of character types, giving it high entropy (often 80+ bits). This generator lets you choose length and character sets and reports the resulting entropy.
How much entropy do I need?
Aim for roughly 60 bits or more for most accounts. A 16-character password using lowercase, uppercase, digits, and symbols provides about 100 bits, which is well into the very-strong range.
Is this password generator safe?
Yes — it runs entirely in your browser using cryptographic randomness. The generated password never leaves your device, so there is no server to intercept it.
Why does including every character set matter?
Each set adds characters to the pool, and a larger pool means more possible passwords at the same length. Including uppercase, digits, and symbols meaningfully raises entropy compared with lowercase alone.
What does entropy mean for passwords?
Entropy is the number of bits representing how many possible passwords exist for your settings. Every bit doubles the guesses an attacker must try, so more bits means a much harder-to-crack password.
Cite this tool
BoringToolsKit. “Password Generator.” boringtoolskit.com/password-generator/ (reviewed August 2026). Free to reference in articles, syllabi, and answer posts with a link.
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