🔍 Password Strength Checker

How Does This Password Strength Checker Work?

🔒 Your privacy is absolute — 100% local analysis

Your password is analyzed entirely in your browser using JavaScript. It is never sent to any server, never stored anywhere, and never transmitted over the internet. You can verify this by pressing F12 → Network tab or by disconnecting from the internet — the tool will continue working perfectly. This is the safest way to test your password strength.

⏱️ How is the brute force crack time calculated?

The estimated crack time is based on:

• Character pool size: how many different characters are possible (lowercase = 26, + uppercase = 52, + digits = 62, + symbols = 95).
• Password length: each additional character multiplies the total combinations exponentially — this is why length is the most important factor.
• Attack speed: we assume 100 billion attempts per second, which represents specialized cracking hardware such as GPU clusters used by professional attackers.
• Formula: Total combinations = (character pool)^length. Crack time = total combinations ÷ attack speed.

📊 What is password entropy and how many bits do you need?

Entropy measures the "randomness" or "unpredictability" of your password in bits. It's calculated as log2(pool_size ^ length). The more entropy bits, the exponentially harder it is to crack. Here's a reference guide:

• Less than 28 bits: very weak — cracked in seconds by any attacker.
• 28–35 bits: weak — cracked in minutes to hours.
• 36–59 bits: moderate — could take days to months.
• 60–127 bits: strong — years to centuries to crack.
• 128+ bits: very strong — practically impossible with any current or foreseeable technology.

🔑 What makes a password truly secure?

• Length: at least 12 characters, ideally 16+ according to NIST guidelines.
• Variety: mix uppercase, lowercase, numbers, and special symbols.
• Randomness: no dictionary words, names, dates, keyboard patterns, or predictable substitutions.
• Uniqueness: a different password for every account — reusing passwords enables credential stuffing attacks.

🛡️ How to improve your password security

If your password scored poorly, here's what you should do:

• Generate a random password — our generator uses military-grade cryptography to create uncrackable passwords.
• Use a password manager — store all your unique passwords securely encrypted.
• Enable two-factor authentication (2FA) — adds a second layer even if your password is compromised.
• Check if your email has been leaked — find out if your accounts have been exposed in data breaches.
• Consider passphrases — easier to remember and can be equally secure when long enough.