Password generator
Configure your character set and length, then generate one or many strong passwords instantly — all in your browser, never sent to a server.
About this tool
The strength of a password is measured in entropy — the number of bits of genuine unpredictability it contains — and human-chosen passwords have far less than they appear to. Substituting 3 for e and appending a 1 and an exclamation mark adds almost nothing, because password-cracking tools apply exactly those transformations first. A random password's entropy is calculable: it is the length multiplied by the base-2 logarithm of the alphabet size. Sixteen characters drawn from the full 94-character printable ASCII set gives about 105 bits, which is beyond brute force by any foreseeable margin. The same length drawn only from lowercase letters gives 75 bits, which is still strong but no longer astronomically so. Length buys more than complexity: adding a character multiplies the search space, while adding a character class only widens the base. This generator uses the browser's crypto.getRandomValues, a cryptographically secure source, rather than Math.random, which is predictable from a handful of outputs and must never be used for secrets. Length and character sets are configurable, and passwords are generated locally — none are transmitted or stored.
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Choose your desired password length using the slider.
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Toggle character sets — uppercase, lowercase, numbers, and symbols — to meet your site's requirements.
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Click Generate to create one or more passwords instantly.
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Click Copy next to any password to copy it to your clipboard.
Generate strong unique passwords for every account to avoid credential reuse.
Create bulk passwords for provisioning new user accounts or test environments.
Quickly produce a high-entropy passphrase that meets complex site requirements.
Strong 16-char password
Length: 16, all typesG7#kPm!2xQr9&nVzDigits-only PIN
Length: 6, numbers only483920No-symbols password
Length: 12, upper + lower + numbersJk3mXpR8qTn5The site rejects the generated password
Cause: Many sites impose an undocumented maximum length or ban particular symbols, and some silently truncate rather than reject — which means the password you saved is not the one the site stored.
Fix: Turn off symbols and reduce the length to fit the site's rules, then compensate with extra length if it is allowed. If a site truncates silently, you will only discover it when login fails; test the saved password once before relying on it.
Reusing one strong password everywhere
Cause: A single reused password means one breached site compromises every account sharing it, and credential-stuffing attacks automate exactly this at scale. Strength offers no protection against reuse.
Fix: Generate a unique password per site and store them in a password manager. The only password worth memorising is the vault's master password, which should be a long passphrase.
Losing the password after generating it
Cause: Nothing is stored here. The password exists only in the browser tab, and closing or refreshing it is unrecoverable.
Fix: Copy the password into your password manager before navigating away. Never store generated passwords in a plain-text note, a spreadsheet, or a chat message to yourself.
These answers explain common password gen tasks, expected input formats, and edge cases so both visitors and search engines can understand what this tool does.
How random are the generated passwords?
Passwords are generated using the Web Crypto API (crypto.getRandomValues), which provides cryptographically secure randomness — the same source used by password managers.
What does entropy mean?
Entropy measures how unpredictable a password is, expressed in bits. A 128-character set with a 16-character password gives about 112 bits of entropy — effectively uncrackable with current hardware.
Are the passwords sent anywhere?
No. Everything runs locally in your browser. No password ever leaves your device.
How many passwords can I generate at once?
Up to 20 passwords in a single batch using the count slider.