Password Generator

Generate strong, random passwords, memorable passphrases, or PINs — with a live entropy meter and crack-time estimate. Plus a built-in password strength checker.

🔒 Crypto-secure randomness 🚫 Never sent anywhere ⚡ Instant
Click Generate
Entropy: Crack time (offline attack):
Length
Characters16
Character Types
Uppercase (A-Z)
Lowercase (a-z)
Numbers (0-9)
Symbols (!@#$…)
Rules
Exclude ambiguous (0,O,1,l,I,|)
No repeating characters
No sequential (abc, 123)
Begin with a letter
Custom
Bulk Results
🔍 Check Your Own Password's Strength
Entropy: Crack time (offline attack):

🔒 This field never submits anywhere — the check happens entirely in your browser as you type.

How This Tool Keeps Your Passwords Private

Every password, passphrase, and PIN on this page is generated using window.crypto.getRandomValues() — the same cryptographically secure random number source browsers use for encryption. This is fundamentally different from Math.random(), which is not secure enough for passwords because its output can be predicted.

Nothing you generate or type here — including in the strength checker above — is sent to any server, logged, stored, or transmitted anywhere. The entire page runs as static JavaScript in your browser. You can verify this yourself by opening your browser's developer tools (Network tab) while using this page — you'll see zero requests related to password generation or checking.

💡 Best practice: Generate your password here, then immediately save it in a password manager (Bitwarden, 1Password, or your browser's built-in manager). You shouldn't need to remember most of your passwords — only your password manager's master password (use a passphrase for that one).

Understanding Password Entropy & Crack Time

Entropy measures how unpredictable a password is, expressed in bits. It's calculated as: length × log₂(character pool size). A longer password, or one drawn from a larger set of possible characters, has more entropy — and each additional bit of entropy doubles the number of guesses an attacker needs to try.

EntropyStrengthCrack time @ 10 billion guesses/secExample
< 28 bitsVery WeakInstantpassword123
28-35 bitsWeakSeconds to minutesSunshine22
36-59 bitsFairHours to monthsTr0ub4dor&3
60-79 bitsGoodDecades to centuries12-character random
80-99 bitsStrongMillions of years16-character random
100+ bitsVery StrongEffectively uncrackable20+ character random, 6-word passphrase

The crack-time estimate above assumes 10 billion guesses per second — a realistic worst-case for an attacker running modern GPUs against a database of weakly-hashed (fast-hash) passwords. Well-implemented sites use slow hashing algorithms like bcrypt or Argon2, which can reduce guess rates to a few thousand per second — making even "Good" passwords effectively secure in practice. But since you can't control how a site stores your password, aim for "Strong" or "Very Strong" for anything important.

Random Password vs Passphrase vs PIN — Which Should You Use?

🎲 Random Passwords

Maximum entropy per character — a 16-character password using all four character types (upper, lower, numbers, symbols) has about 105 bits of entropy. Best for accounts where you'll copy-paste from a password manager rather than type manually. This is the right default for the vast majority of your accounts.

📝 Passphrases

Multiple random words strung together — easier to type and remember than random characters, while still reaching strong entropy levels with enough words. A 6-word passphrase from a reasonably sized word list provides roughly 60-77 bits of entropy depending on the word list size. Best for passwords you need to type from memory — like your password manager's master password, or your device's login password.

🔢 PINs

Short numeric codes — inherently lower entropy (a 6-digit PIN has about 20 bits, or roughly 1 million combinations). PINs are appropriate only where the system limits guess attempts, such as phone lock screens, bank cards, or door codes with lockout policies. Never use a PIN as a website password.

Password Best Practices for 2026

Use a unique password for every account. If one service is breached and your password is exposed, attackers immediately try that same password on other sites — a technique called "credential stuffing." A password manager makes unique passwords for every account practical.

Prioritize length over complexity. A 20-character password using only lowercase letters has more entropy than an 8-character password with every character type. Modern password requirements that mandate "at least one symbol" but cap length at 12 are actually weaker than longer, simpler passwords.

Enable two-factor authentication (2FA) wherever available. Even a strong password can be phished. 2FA — especially an authenticator app or hardware key rather than SMS — adds a critical second layer that protects you even if your password is compromised.

Don't reuse your email password anywhere else. Your email account is often the recovery method for every other account — if it's compromised, an attacker can reset passwords on all your other services.

⚠️ Avoid these common patterns: appending numbers to a word (password1, password2), simple letter-to-symbol substitutions (p@ssw0rd), keyboard patterns (qwerty, asdf1234), and personal information (names, birthdates, pet names). These patterns are the first things password-cracking dictionaries check, regardless of how "clever" they feel.

Frequently Asked Questions

Is this password generator safe to use?
Yes. It uses your browser's built-in cryptographically secure random number generator (window.crypto.getRandomValues) — the same source used for encryption. Every password is generated entirely on your device; nothing is sent to, logged by, or stored on any server. You can verify this in your browser's developer tools.
What makes a strong password?
Length, randomness, and uniqueness. A strong password is 16+ characters, not based on dictionary words or personal information, and not reused across accounts. Length matters more than complexity — a longer simple password often beats a shorter complex one.
What is password entropy?
Entropy measures randomness in bits: length × log₂(character pool size). Each additional bit doubles the possible combinations an attacker must try. Aim for 80+ bits for important accounts — our entropy meter updates live as you adjust settings.
How long should my password be?
16+ characters with mixed character types for most accounts. 20+ characters or a 6-word passphrase for critical accounts like your password manager or email. Check the target site's maximum length first — some cap it lower than you'd expect.
Should I use a password or a passphrase?
Both can be very secure. Random passwords pack more entropy per character but are hard to type — best for password-manager-stored accounts. Passphrases (multiple words) are easier to type and remember — best for your master password or device login, where you need to type from memory.
What does crack time mean?
An estimate of how long brute-forcing your password would take, based on its entropy and an assumed 10 billion guesses/second (a realistic GPU-based attack on a fast-hashed password database). It's a worst-case estimate — well-designed sites using slow hashing make actual cracking far slower.
Why exclude ambiguous characters?
Characters like 0, O, 1, l, and I can look identical in some fonts, making manually-typed passwords error-prone. Excluding them slightly reduces entropy but helps when you need to read and type a password rather than paste it.
How often should I change my passwords?
Current guidance (NIST 2025) recommends against routine forced changes, which often lead to weaker, predictable passwords. Change a password immediately if: the service reports a breach, you've shared it, you suspect compromise, or you discover it's reused elsewhere. A strong unique password doesn't need periodic rotation otherwise.

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