What makes a strong password?
Length matters most. A 16-character password using uppercase, lowercase, numbers and symbols would take an attacker an impractically long time to guess. Avoid names, birthdays and dictionary words, and never reuse the same password on multiple sites.
Is this generator safe?
Yes. Passwords are created in your browser using the Web Crypto API (crypto.getRandomValues), a cryptographically secure random generator. They are never sent or stored anywhere.
Tip
Use a password manager to remember your passwords so every account can have a unique one.