Guide
How to Create a Strong Password — Security Guide
Weak passwords are the number one cause of account breaches. Despite years of security advice, the most commonly used passwords are still '123456' and 'password'. This guide explains what actually makes a password secure, debunks common myths, and shows you how to generate unbreakable passwords instantly.
Last updated: April 17, 2026
What Makes a Password Strong?
Password strength comes down to one thing: how many guesses it would take an attacker to crack it. This is determined by length and randomness (entropy). A truly random 16-character password using uppercase, lowercase, numbers, and symbols has approximately 10^30 possible combinations — more than the number of grains of sand on Earth.
The key insight is that length matters more than complexity. A random 20-character lowercase-only password (26^20 combinations) is astronomically stronger than a complex 8-character password with special characters (95^8 combinations). Modern security guidance has shifted from 'make it complex' to 'make it long and random'.
Common Password Mistakes
- Using personal information — Names, birthdays, pet names, and anniversaries are easily guessable through social media.
- Simple substitutions — Replacing 'a' with '@' or 'o' with '0' adds almost no security. Attackers' tools account for these patterns.
- Dictionary words — Even uncommon words are vulnerable to dictionary attacks. 'Chrysanthemum' looks complex but is trivially cracked.
- Reusing passwords — If one service is breached, attackers try the same credentials on every other service. One breach becomes many.
- Short passwords — Any password under 12 characters can be brute-forced with modern hardware in hours or days.
- Pattern-based passwords — Keyboard patterns like 'qwerty', '1qaz2wsx', or 'abc123' are among the first things attackers try.
How to Generate Secure Passwords
- Step 1: Use our Password Generator at /developer-tools/password-generator to create cryptographically random passwords.
- Step 2: Set the length to at least 16 characters. For critical accounts (email, banking), use 20+.
- Step 3: Include uppercase, lowercase, numbers, and symbols for maximum entropy per character.
- Step 4: Generate a unique password for every account. Never reuse passwords across services.
- Step 5: Store passwords in a password manager (Bitwarden, 1Password, or KeePass). You only need to remember one master password.
The Passphrase Alternative
If you need a password you can memorize, use a passphrase — a sequence of 4-6 random words. For example: 'correct horse battery staple' (famously illustrated by XKCD) has high entropy while being memorable. The key is that the words must be truly random, not a meaningful sentence.
A 5-word passphrase from a 7,776-word dictionary (like the Diceware list) provides approximately 64 bits of entropy — equivalent to a random 10-character password with mixed character types. For even more security, add a random number or symbol between words.
Two-Factor Authentication (2FA)
Even the strongest password can be compromised through phishing, keyloggers, or service breaches. Two-factor authentication adds a second layer: something you have (phone, security key) in addition to something you know (password).
Enable 2FA on every account that supports it, especially email, banking, cloud storage, and social media. Authenticator apps (Google Authenticator, Authy) are more secure than SMS codes, and hardware security keys (YubiKey) provide the strongest protection.
Frequently Asked Questions
- Q: How often should I change passwords? — Only when you suspect a breach. Frequent forced changes lead to weaker passwords. Use unique, strong passwords and a password manager instead.
- Q: Are password managers safe? — Yes. Reputable password managers encrypt your vault with your master password. Even if the manager's servers are breached, your encrypted data is useless without the master password.
- Q: Can I check if my password was leaked? — Yes. Services like haveibeenpwned.com check your email against known breaches. Our Password Generator creates passwords that are guaranteed unique.
- Q: What's the minimum secure password length? — 12 characters minimum for general accounts. 16+ for email, banking, and accounts containing sensitive data. 20+ for critical infrastructure.
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