Password Strength Checker

Test how long it would take an attacker with modern hardware to crack your password. Calculates Shannon entropy, time-to-crack against a 10 billion-guesses-per-second offline attack, and checks against common patterns.

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Why Password Strength Matters

Modern attackers don't guess passwords through a website's login screen — they steal a database of password hashes (from a breach) and crack them offline using GPUs that try 10 billion or more guesses per second. Entropy, measured in bits, captures how many guesses are needed on average. Each extra bit doubles cracking time. A 12-character random password mixing all four character classes has about 78 bits of entropy — strong enough to resist offline brute force for centuries. An 8-character lowercase-only password has 38 bits and falls in seconds. Password managers generate truly random high-entropy passwords so you don't have to remember them.

Best Password Management Tools

The easiest way to use strong, unique passwords on every account is to let a password manager generate and store them for you:

• 1Password →

  Premium password manager with strong family/team plans, Travel Mode, and Watchtower breach monitoring.

• Bitwarden →

  Open-source password manager with a generous free tier and self-hosting option for the security-conscious.

• Dashlane →

  Password manager bundled with VPN and dark-web monitoring; popular for SMB and enterprise rollouts.

• Best Free Cybersecurity Tools →

  Curated list of the best free security tools, including password managers, MFA apps, and breach monitors.