Strong Password Generator
Create a strong password and see exactly how strong it is, measured in bits of entropy. Free, private, no sign-up.
What "strong" actually means
Password strength is not about how complicated a password looks — it is about how much work guessing takes. The precise measure is entropy: password length multiplied by log₂ of the character pool size. Each bit of entropy doubles the attacker's work. A password with 40 bits of entropy can fall in seconds to a modern GPU; one with 128 bits is beyond brute force for the foreseeable future. This password generator shows the entropy of every password it creates, so you are not guessing about strength — you can see it.
Length vs. complexity
Both help, but length helps more. Adding one character multiplies the search space by the entire pool (70+ with all sets enabled), while adding a character set only enlarges the pool modestly. Practical advice: when a site allows symbols, use them; when it does not, compensate with four to six extra characters. A 24-character password from a smaller pool routinely beats a 12-character one from a larger pool.
Reading the strength meter
After generating, the tool labels the result (for example "Very strong") and shows the exact entropy in bits. Treat anything above 80 bits as safe from brute force; this generator comfortably reaches 100–130 bits at its defaults. Remember that the meter measures resistance to guessing — it cannot protect a password you reuse across sites or type into a phishing page.
Strong and unique: the password-manager habit
The strongest password in the world fails if you reuse it, because one breached site hands it to attackers everywhere. The workflow that actually works: generate a fresh, random password per account — see our random password generator for why randomness matters — and let a password manager remember them. You memorize one master password; the manager handles the rest.
Private by design
Strength estimation and generation both run locally in your browser. Your candidate passwords never leave the tab, are never uploaded, and are never stored. Close the tab and they are gone.
Frequently asked questions
What makes a password "strong"?
Strength is measured as entropy: length × log₂ of the character pool size. More entropy means exponentially more guessing work. A random 20-character password from all four sets has about 130 bits of entropy — uncrackable by brute force with any foreseeable hardware.
Is a longer password better than a complex one?
Length usually wins. Each extra character multiplies the search space by the pool size. When a site restricts symbols, add length instead: a 24-character lowercase-only password beats a short complex one.
How long would it take to crack my password?
The strength meter translates entropy into a plain-English label. As a rule of thumb, anything above 80 bits is beyond brute force; this tool makes 100+ bits easy. The real risks are reuse and phishing, not brute force.
Is "Password123!" strong?
No. It uses common patterns that cracking dictionaries try within seconds. Strength comes from randomness, not from swapping letters for symbols in a predictable word.
Does the generator store my password?
No. Everything runs in your browser and nothing is uploaded, logged, or remembered.
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