Generate strong, random passwords instantly. Choose your length, character sets, and how many passwords you need. No data is sent to any server: all passwords are generated entirely inside your browser and are never stored or transmitted. Free, private, and instant.
Password strength is primarily about entropy, which is a measure of unpredictability. A password's entropy is determined by two things: how long it is, and how many different characters it could use at each position. A 16-character password using uppercase letters, lowercase letters, numbers, and symbols draws from a pool of around 90 characters. Each additional character in the password multiplies the number of possible combinations by 90. A 16-character password from this pool has approximately 90^16 (roughly 10^31) possible values, which would take billions of years to crack by brute force even with very fast hardware.
Length matters more than complexity. A 20-character password using only lowercase letters is stronger than a 10-character password using all character types. Both are far stronger than any real word or phrase with deliberate substitutions like "P@ssw0rd", which password cracking software tests within seconds.
Yes. All passwords generated on this page are created entirely inside your browser using JavaScript's window.crypto.getRandomValues() function where available, which is cryptographically secure. No password is ever sent to any server, stored in a database, or transmitted anywhere. You can verify this by disconnecting from the internet and the generator will continue to work. The only way this tool could be unsafe is if someone else can see your screen.
A passphrase is a sequence of random words, such as "Correct-Horse-Battery-Staple". This concept was popularised by security researcher Bruce Schneier and the webcomic XKCD. A four-word passphrase from a vocabulary of 7,776 common words (a standard wordlist) has about 51 bits of entropy, similar to a random 9-character password using mixed case and symbols. A five-word passphrase has about 64 bits, equivalent to a random 12-character password. Passphrases are often easier to remember while being genuinely strong.
Every online account should have a unique password. If you reuse the same password across multiple sites and one site is breached, attackers will immediately try your password on every other major service. This attack, called credential stuffing, is one of the most common ways accounts are compromised. The solution is a password manager (such as Bitwarden, 1Password, or the one built into your browser) that stores a different strong password for every account. Use this generator to create those passwords, and store them in the manager.
The most commonly breached passwords in NZ include birthdays, suburb names, sports team names, and simple keyboard patterns. "Wallabies", "Auckland2024", and "Warriors123" are all extremely weak. IRD, MyIR, online banking, email, and the NZ government RealMe identity service are the highest-risk accounts to protect because they can affect your financial and legal identity. Use a unique 16+ character random password for each of these services, and enable two-factor authentication (2FA) wherever possible.
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