Is this password generator safe?

Yes — passwords are generated locally using crypto.getRandomValues(). Nothing is sent to any server.

What is password entropy?

Entropy = length × log₂(pool size). Higher bits means exponentially more combinations for an attacker to try.

How long should my password be?

At least 12–16 characters. Length is the most important factor.

Should I use a passphrase or random password?

Both are good. Passphrases are easier to remember; random passwords are more compact for the same entropy.

Why should I use unique passwords?

Reused passwords enable credential stuffing: one breach exposes every account sharing that password.

Security

Strong password generator

Instantly generate strong, random passwords or memorable passphrases. Customize length, character types, and see real-time entropy and strength rating. Passwords are generated entirely in your browser — nothing is ever stored or transmitted.

Live generation Entropy bits 5-tier strength meter Passphrase mode Character pool preview Never stored

Password Generator

Strong, random, browser-only

Length 16

4326496128

Character Types

abc Lowercase

ABC Uppercase

123 Numbers

!@# Symbols

0Ol Exclude ambiguous (0, O, l, 1, I)

Pool 95 chars

Strength —

— bits

Generate a password to see its strength.

Generated Password

—

Password Generator — Secure & Random

This free password generator creates cryptographically random passwords using your browser's built-in crypto.getRandomValues() API. Every password is generated locally on your device — no server, no storage, no transmission.

Choose your length (4–128 characters), enable or disable lowercase letters, uppercase letters, numbers, and symbols. Switch to passphrase mode to generate a string of random words — memorable yet highly secure. The entropy display and strength meter update instantly as you adjust any setting.

What Makes a Password Strong?

Length Every extra character multiplies the search space. 16+ characters is recommended for critical accounts.

Randomness Truly random passwords (not keyboard walks or word substitutions) resist dictionary and pattern attacks.

Character variety Using all four character types (lower, upper, digits, symbols) maximises the pool each character draws from.

Uniqueness Never reuse passwords. One breached site exposes every account sharing that password.

Password Entropy & Crack Time

Entropy in bits = length × log₂(pool size). Higher entropy means exponentially longer crack times:

Length	Character set	Pool	Entropy	Strength
8	Lowercase only	26	37.6 bits	Very Weak
8	Lower + Upper + Digits	62	47.6 bits	Weak
12	Lower + Upper + Digits	62	71.4 bits	Fair
16	All types (95 chars)	95	105.0 bits	Strong
20	All types (95 chars)	95	131.2 bits	Very Strong

Passphrase Mode — Memorable & Secure

A passphrase is a sequence of random words such as "correct-horse-battery-staple". Because each word is chosen randomly from a large wordlist, a 4-word passphrase from a 2,048-word list has about 44 bits of entropy — comparable to a random 8-character password with all character types. A 6-word passphrase exceeds 66 bits.

Why passphrases work

Humans remember strings of words far better than random characters. Combined with a separator (dash, dot, or number), passphrases are both highly secure and practical to remember without a password manager — ideal for master passwords or device unlock pins.

Frequently Asked Questions

Yes — passwords are generated entirely in your browser using the Web Crypto API (crypto.getRandomValues()). No data is sent to any server. You can even disconnect from the internet and use this page.

Entropy measures unpredictability in bits. It equals: length × log₂(pool size). A pool of 95 printable ASCII characters gives log₂(95) ≈ 6.57 bits per character. A 16-character all-types password therefore has ~105 bits of entropy — meaning an attacker would need to try 2¹⁰⁵ combinations on average to guess it by brute force.

At minimum 12 characters for everyday accounts; 16+ for sensitive accounts like email, banking, and password managers. Length is the single biggest factor — each additional character multiplies the search space by the pool size.

Both are excellent. Random character passwords are slightly more compact for the same entropy. Passphrases are easier to remember and type, making them ideal for master passwords or any account where you need to recall the password without a manager.

If one site is breached and you reuse a password, attackers try that same credential on every other site (a "credential stuffing" attack). Unique passwords mean a single breach cannot cascade across your other accounts.

The symbol set is: !@#$%^&*()_+-=[]{}|;':",<>?/`~\. — 32 printable special characters from the standard ASCII range. You can see the active character pool in the pool preview panel below the toggles.

Yes — the generator is fully responsive and works on any modern smartphone or tablet browser. The one-click copy button works on iOS and Android via the Clipboard API with a fallback for older browsers.

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