Security
20 Character Password Generator
Generate strong 20-character passwords instantly. 20 characters with mixed types gives ~131 bits of entropy — effectively uncrackable. Free, browser-based, no signup.
About this 20 character password generator
A 20-character random password with uppercase letters, lowercase letters, numbers, and symbols provides approximately 131 bits of entropy. To put that in perspective: even if every computer on Earth attempted a trillion guesses per second, cracking it would take longer than the current age of the universe. The NIST Digital Identity Guidelines recommend at least 15 characters for general accounts — 20 characters gives you a significant safety margin above that threshold. Twenty characters is also the sweet spot between security and usability: long enough to be essentially uncrackable, short enough to copy-paste or type without excessive effort. This generator defaults to exactly 20 characters with all four character sets enabled, producing the highest-entropy output this length allows.
FAQ
Common questions
How secure is a 20-character password?
A 20-character password using all character types has approximately 131 bits of entropy. At 10 billion guesses per second (a high-end GPU attack), cracking it would take around 10²⁰ years — effectively impossible with any foreseeable technology.
Is 20 characters enough for all accounts?
Yes — 20 characters exceeds the NIST recommendation of 15 characters and is sufficient for any current use case including banking, email, and cloud storage. For extremely sensitive accounts, you can go up to 32 or 64 characters.
Do all websites accept 20-character passwords?
Most modern websites accept passwords up to 64 characters (NIST recommendation for maximum length). Some older systems have lower limits — typically 32 or 20 characters. If a site rejects your password, try reducing to 16 characters first.
What is the entropy of a 20-character password?
With 95 printable ASCII characters available (uppercase, lowercase, digits, symbols), each character contributes log₂(95) ≈ 6.57 bits of entropy. 20 characters × 6.57 = ~131 bits total.
Should I use 20 characters or a passphrase?
A 20-character random password is stronger per character but impossible to memorize. Use it for any password stored in a manager. Use a passphrase only for the few passwords you must type manually — like your password manager master password.
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