Generate strong, random passwords with custom length and character sets. Include uppercase, lowercase, numbers, and symbols. Free online password generator.
The Password Generator creates strong, random passwords with customizable length and character sets. Choose from uppercase letters, lowercase letters, numbers, and special symbols to create passwords that meet any security requirement.
Weak passwords are the leading cause of security breaches. A strong password should be at least 12 characters long, include multiple character types, and be unique for every account.
This generator uses JavaScript's Math.random() to assemble passwords from your selected character set. Each character is chosen independently, maximizing entropy. The tool also estimates password entropy in bits to help you gauge strength.
Precise measurement of this value supports better personal and professional planning, helping you make informed decisions about how to prioritize tasks and manage competing demands. Quantifying this parameter enables meaningful comparison across time periods and projects, revealing trends that inform better decisions about personal productivity and resource management.
Precise measurement of this value supports better personal and professional planning, helping you make informed decisions about how to prioritize tasks and manage competing demands.
Humans create predictable passwords. This generator produces truly random passwords with high entropy, making them resistant to brute-force and dictionary attacks. Regular monitoring of this value helps individuals and teams detect productivity patterns and adjust workflows before small inefficiencies become entrenched and hard to correct. Having accurate figures readily available simplifies project planning, deadline negotiation, and workload balancing conversations with managers, clients, and team members.
Entropy = length × log₂(pool_size) Pool size examples: - Lowercase only: 26 - + Uppercase: 52 - + Numbers: 62 - + Symbols: ~94
Result: e.g. k7#Tz!mQ9&xR4wLp
A 16-character password using all character types (94 pool) has about 105 bits of entropy. Brute-forcing this would take billions of years.
Entropy in bits = password length × log₂(character pool size). A 94-character pool (all printable ASCII) gives ~6.55 bits per character. 80+ bits of entropy is considered strong.
Dictionary attacks try common words and patterns. Brute-force attacks try every combination. Rainbow tables precompute hashes. Random passwords defend against all three methods.
An alternative to random characters is a passphrase: 4–6 random words (e.g., "correct horse battery staple"). Passphrases can be strong and memorable, with entropy depending on the word list size.
Consistent practice with varied problems builds computational fluency and deepens conceptual understanding that transfers across many technical fields.
At least 12 characters for general use, 16+ for high-security accounts. Each additional character exponentially increases cracking difficulty.
Entropy measures the unpredictability of a password in bits. Higher entropy means harder to crack. A 12-character mixed password has about 79 bits of entropy.
Special characters increase the pool size from 62 (letters+numbers) to about 94, adding about 6 bits of entropy per character. This makes cracking much harder.
For most purposes, yes. Math.random() is pseudo-random but sufficient for password generation. For cryptographic-grade randomness, use a dedicated security tool.
An attacker tries every possible combination. At 1 billion guesses per second, a 12-character mixed password (79 bits) would take about 19 million years.
Absolutely. A password manager lets you use unique, complex passwords for every account without memorizing them. It is the single best step to improve your security.