How to Create Strong Passwords (and Why Length Wins)
What actually makes a password strong, why length beats complexity, and how to generate and manage passwords you don't have to memorize.
A strong password is long and unpredictable. Length matters more than symbols: each extra character multiplies the number of guesses an attacker needs. The best approach is a password manager generating 16+ random characters, unique per site.
Most password advice is outdated. Forcing a capital letter, a number, and a symbol produces passwords that are hard for humans and easy for computers. Here’s what actually matters.
Strength = entropy
Password strength is measured in entropy — the number of bits of randomness. More bits means exponentially more guesses to crack. Entropy depends on two things:
- The size of the character pool you draw from.
- How many characters long the password is.
Length has an outsized effect because it’s an exponent. Adding one lowercase character multiplies the search space by 26; adding a whole word’s worth of characters multiplies it enormously.
A quick comparison
| Password style | Example | Approx. entropy |
|---|---|---|
| 8 chars, mixed | Tr0ub4d! | ~40 bits (weak) |
| 4 random words | river-atlas-copper-nine | ~52 bits |
| 20 random chars | generated | ~120+ bits (very strong) |
Practical rules
- Go long. Aim for 16+ characters, or a 4–5 word passphrase.
- Make it unique. Never reuse a password across sites — one breach shouldn’t unlock everything.
- Let a tool do it. Humans are bad at randomness. A generator using a cryptographically secure RNG is far better.
You can generate one right now with our Password Generator. It uses the browser’s secure random source and shows a live entropy estimate — nothing is transmitted or stored.
Then use a password manager
The only realistic way to have a unique, long password for every account is a password manager. It generates and stores them, so you memorize exactly one strong master password (make that a long passphrase).
Turn on two-factor authentication wherever you can. Even a leaked password is far less useful to an attacker when a second factor is required.
Takeaways
- Prioritize length over forced complexity.
- Use a unique password per site.
- Generate with a secure tool and store them in a password manager.
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