Password Generator
Generate strong, cryptographically secure passwords instantly with our Password Generator. Create random passwords with customizable length and character sets including uppercase letters, lowercase letters, numbers, and special symbols. The tool uses the browser's built-in crypto API to ensure true randomness and maximum security. Perfect for creating new account passwords, updating old credentials, or generating API keys. Toggle options to exclude ambiguous characters like O/0 and l/1 that can be easily confused. Copy your generated password with one click and use it immediately. All generation happens locally in your browser—no passwords are ever stored, logged, or transmitted. Create unlimited passwords for free with no restrictions. Ideal for anyone serious about online security and password hygiene.
How it works: Generates cryptographically secure random passwords using the Web Crypto API. Customize length (8-64 characters) and character types. Never reuse passwords across different sites.
Overview
Generate strong, cryptographically secure passwords instantly with our Password Generator. Create random passwords with customizable length and character sets including uppercase letters, lowercase letters, numbers, and special symbols. The tool uses the browser's built-in crypto API to ensure true randomness and maximum security. Perfect for creating new account passwords, updating old credentials, or generating API keys. Toggle options to exclude ambiguous characters like O/0 and l/1 that can be easily confused. Copy your generated password with one click and use it immediately. All generation happens locally in your browser—no passwords are ever stored, logged, or transmitted. Create unlimited passwords for free with no restrictions. Ideal for anyone serious about online security and password hygiene.
About
About Password Generator
Generate strong, cryptographically secure passwords instantly. Create random passwords with customizable length and character sets. The tool uses the browser's Web Crypto API for true randomness and maximum security.
Features:
- Cryptographically secure randomness
- Custom length (8-64 characters)
- Uppercase letters option
- Lowercase letters option
- Special symbols option
- One-click copy
- 100% private - no data stored
FAQ
Is randomness secure?
Yes. We use the browser's crypto API for secure randomness.
Can I avoid ambiguous characters?
Yes. Toggle to exclude look-alikes like O/0 and l/1.
Do you store any passwords?
No. Everything runs locally in your browser.
Related Tools
What Is a Password Generator?
A password generator creates cryptographically random passwords by combining characters from specified sets — uppercase letters, lowercase letters, digits, and special characters. Unlike human-chosen passwords (which follow predictable patterns), computer-generated passwords have maximum entropy for their length, making them far more resistant to brute-force and dictionary attacks.
Password strength is measured in bits of entropy — the logarithm of the number of possible combinations. A 16-character password using all character types has ~104 bits of entropy, meaning there are 2¹⁰⁴ ≈ 20 septillion possible combinations. Even at 100 billion guesses per second, cracking it would take longer than the age of the universe.
How to Use This Password Generator
- Set your desired password length (minimum 12 characters recommended; 16+ for sensitive accounts).
- Select character types: uppercase letters (A–Z), lowercase (a–z), numbers (0–9), and/or special characters (!@#$%^&*).
- Click “Generate” to create a new random password. Click multiple times to generate options.
- Click the copy icon to copy the password to your clipboard, then paste it directly into your password manager.
- Never store the password by typing it in a document — use a dedicated password manager (Bitwarden, 1Password, etc.).
Worked Example: Password Entropy Calculation
Character pool size determines entropy. For a 16-character password:
Lowercase only (26 chars): 26¹⁶ = 43-bit entropy → crack in minutes
Lowercase + digits (36 chars): 36¹⁶ = 83-bit entropy → crack in years
All types (95 chars): 95¹⁶ = 105-bit entropy → crack in trillions of years
Formula: Entropy = log₂(character pool size) × password length. Adding even one character type dramatically improves security.
Password Strength vs. Crack Time Reference
| Password Example | Length | Entropy | Crack Time (100B/sec) |
|---|---|---|---|
| password | 8 | < 28 bits | < 1 second (in top-10 lists) |
| Password1 | 9 | ~43 bits | < 1 second (dictionary attack) |
| Tr0ub4dor | 9 | ~53 bits | ~3 hours (l33t-speak known) |
| xK#9mP2$v | 12 | ~79 bits | ~200 years |
| K9#mP2$vL7@n | 16 | ~105 bits | Trillions of years |
| Correct-Horse-Battery | 20 | ~76 bits (words) | ~500 years (passphrase) |
Crack times assume online brute-force at 100 billion guesses/second. Offline attacks (stolen hash databases) can be billions of times faster — making length and randomness even more critical.
Key Concepts: Entropy, Salt, and Password Hashing
Password entropy is the measure of how unpredictable a password is, in bits. Each added bit doubles the search space. A 40-bit password has 1 trillion combinations; a 80-bit password has 1 trillion trillion. Modern recommended minimums are 60+ bits for most accounts and 80+ bits for financial/email accounts that can be used to reset other passwords.
Why unique passwords matter. When a website is breached and passwords are stolen (hashed or plaintext), attackers use credential stuffing — trying stolen username/password pairs on thousands of other sites automatically. If you reuse passwords, one breach compromises every account. A password manager generates and stores unique passwords for every site, eliminating this risk.
Two-factor authentication (2FA) as a supplement. Even a strong password can be stolen through phishing, keyloggers, or MITM attacks. 2FA adds a second factor (a time-based code from an authenticator app, a hardware key, or a biometric) that an attacker cannot obtain just by knowing your password. Use strong passwords AND 2FA for critical accounts — email, banking, and any social/work accounts.
Tips for Password Security
Use a password manager. The only practical way to have a unique, random 16-character password for every account is to use a password manager like Bitwarden (free, open-source), 1Password, or Dashlane. You only need to memorize one strong master password. The manager auto-fills credentials and flags reused or breached passwords.
Prioritize security for “gateway” accounts. Your email account is the most critical — it can reset passwords for every other account. Give it the strongest password (20+ characters), enable 2FA with an authenticator app (not SMS), and add a recovery email/phone. Banking, investment, and work accounts come next. Lower-value accounts can have shorter (but still random) passwords.
Check for breached passwords at HaveIBeenPwned.com. This free service (run by security researcher Troy Hunt) checks if your email or passwords appear in known breach databases. If a password shows as compromised, change it immediately — everywhere it was used. Bitwarden and 1Password integrate directly with HaveIBeenPwned to flag compromised saved passwords.
Frequently Asked Questions
How long should a password be?
NIST (National Institute of Standards and Technology) guidelines recommend at least 8 characters minimum, but security experts recommend 12–16+ for most accounts. For high-value accounts (email, banking, password manager master password), use 20+ characters. Length is the single biggest factor in password strength — a 20-character lowercase-only password beats an 8-character mixed-type password.
Is it safe to use an online password generator?
This generator runs entirely in your browser — no passwords are sent to any server. However, any password generator is only as secure as your device and network. For maximum security on high-value accounts, generate passwords on a trusted device on a private network, and paste directly into your password manager without displaying them on screen unnecessarily.
Should I use special characters in passwords?
Yes — special characters (!@#$%^&*) expand the character pool and significantly increase entropy. However, some websites restrict which special characters are allowed. For sites that only allow alphanumeric passwords, compensate with greater length (18+ characters). Special characters do not help if the password is also a common word or pattern.
What is the difference between a password and a passphrase?
A password is a random string of characters (e.g., K9#mP2$v). A passphrase is several random words joined together (e.g., correct-horse-battery-staple — from the famous XKCD comic). Passphrases are easier to remember and type while achieving similar entropy through length. A 4-word passphrase from a 2,048-word list has ~44 bits of entropy — stronger than most human-chosen passwords.
Why shouldn't I reuse passwords?
When sites suffer data breaches (which happen to millions of sites), attackers extract password hashes and crack many of them. They then automatically try those credentials on other popular services (credential stuffing). If you use the same password on multiple sites, one breach cascades into multiple compromised accounts. Unique passwords per site limit breach damage to that one account.
How do I remember all my passwords?
You don't — that's the point. Use a password manager (Bitwarden, 1Password, KeePass) that generates and stores all your passwords. You only memorize one strong master password. The manager auto-fills credentials, works across devices, and alerts you to weak or reused passwords. The only password you truly need to memorize is your email password and your password manager master password.
What makes a password easy to crack?
Common patterns attackers exploit: dictionary words (in any language), common substitutions (e0 for 'o', @ for 'a'), predictable capitalization (first letter only), number appending (Password1!), keyboard patterns (qwerty, 123456), and personal info (birthdate, name, pet name). Any password that includes recognizable words or patterns is vulnerable to rule-based cracking even if it appears complex.
What is multi-factor authentication (MFA) and should I use it?
MFA requires a second proof of identity beyond your password — typically a 6-digit code from an authenticator app (Google Authenticator, Authy) or a hardware security key (YubiKey). Even if your password is stolen, MFA blocks the attacker. Enable MFA on your email, banking, work accounts, and password manager. Use app-based MFA (TOTP) rather than SMS, as SMS can be SIM-swapped.