Password Strength Tester

About Password Strength Tester

The Password Strength Tester is a comprehensive security tool that analyzes password strength using industry-standard algorithms. It evaluates multiple factors including length, character variety, entropy, and common password patterns to provide accurate security ratings.

Our tool helps you create unbreakable passwords by identifying weaknesses and providing actionable recommendations. The built-in password generator uses cryptographically secure random number generation to create truly random, unpredictable passwords.

How is password strength calculated?

Password strength is calculated using multiple factors:

• Length: Longer passwords are exponentially stronger (8+ characters minimum, 12+ recommended)
• Character Variety: Using uppercase, lowercase, numbers, and symbols increases complexity
• Entropy: Mathematical measure of randomness and unpredictability
• Common Patterns: Penalties for dictionary words, sequential characters (abc, 123), and repetitive patterns (aaa, 111)
• Common Passwords: Checks against database of frequently used weak passwords

The final score (0-100) represents overall security, with recommendations for improvement.

What is password entropy?

Entropy measures password randomness in bits. Higher entropy means more possible combinations and better security:

• 0-28 bits: Very Weak (crackable instantly)
• 28-35 bits: Weak (crackable in seconds/minutes)
• 36-59 bits: Fair (crackable in hours/days)
• 60-127 bits: Good (crackable in years)
• 128+ bits: Strong (crackable in centuries)

Entropy = password length × log₂(character set size)

Example: 12-character password with uppercase, lowercase, numbers, and symbols has ~79 bits of entropy.

What is crack time?

Crack time estimates how long it would take to guess your password using brute force attacks (trying every possible combination). The calculation assumes:

• 1 billion password attempts per second (modern hardware capability)
• Trying half of all possible combinations on average
• No additional security measures like rate limiting

Actual crack time varies based on:
• Attacker's computing power
• Whether the password hash is salted
• Implementation of rate limiting
• Use of multi-factor authentication

A good password should take years or centuries to crack.

What makes a password strong?

A strong password has these characteristics:

• Length: At least 12 characters (longer is better)
• Variety: Mix of uppercase, lowercase, numbers, and symbols
• Randomness: No predictable patterns or dictionary words
• Uniqueness: Different password for each account
• Not Reused: Never reused from other services
• Not Personal: Avoid names, birthdays, or personal info

Examples:
❌ Weak: password123, qwerty, abc123
❌ Better but still weak: Password123!
✅ Strong: K9#mL2pQ@vN8xR4t

Why avoid common passwords?

Common passwords are the first ones attackers try because:

• Dictionary Attacks: Hackers use lists of millions of common passwords
• Credential Stuffing: Leaked passwords are reused across sites
• Social Engineering: Personal info makes passwords predictable

Most common passwords include:
• password, 123456, qwerty, abc123
• Names, sports teams, birthdays
• Simple patterns like "password1" or "P@ssw0rd"

Even with complexity (Password123!), common base words remain vulnerable.

What are sequential and repetitive patterns?

Sequential patterns follow predictable orders:
• Alphabetic: abc, xyz, qwerty
• Numeric: 123, 789, 2468
• Keyboard: qwerty, asdfgh

Repetitive patterns repeat characters:
• Same character: aaa, 111, ***
• Repeated segments: abcabc, 123123

Both types significantly reduce password strength because they're easier to guess and appear in common password dictionaries.

How does the password generator work?

Our password generator uses Web Crypto API (window.crypto.getRandomValues()) for cryptographically secure random number generation. This means:

• True Randomness: Uses system entropy sources (hardware noise, mouse movements, etc.)
• Cryptographically Secure: Suitable for security-critical applications
• Unpredictable: Cannot be predicted or reproduced
• Not Pseudo-Random: Unlike Math.random(), which is predictable

You can customize:
• Length (8-64 characters)
• Character types (uppercase, lowercase, numbers, symbols)

Generated passwords are never sent to any server - everything happens locally in your browser.

Is my password safe when I test it?

Yes! Your password is completely safe because:

• Local Processing: All analysis happens in your browser using JavaScript
• No Server Communication: Your password is never sent to any server
• No Storage: No cookies, logs, or database storage
• No Tracking: We don't track or record what you type
• Open Source: The code is transparent and auditable

However, general security advice:
• Don't use real passwords on untrusted websites
• Use this tool to test potential passwords before using them
• Consider using a password manager for storing passwords securely

Should I use a password manager?

Yes! Password managers are highly recommended because they:

• Generate strong, random passwords for each account
• Store passwords securely with encryption
• Auto-fill credentials to prevent phishing
• Alert you to weak or reused passwords
• Work across all devices

Popular password managers:
• 1Password, LastPass, Bitwarden (cross-platform)
• iCloud Keychain (Apple devices)
• Google Password Manager (Chrome/Android)

With a password manager, you only need to remember one strong master password.

What else can I do to stay secure?

Beyond strong passwords, implement these security measures:

• Two-Factor Authentication (2FA): Adds second verification step (SMS, app, hardware key)
• Unique Passwords: Never reuse passwords across sites
• Regular Updates: Change passwords periodically, especially after breaches
• Breach Monitoring: Check if your accounts appear in data breaches (haveibeenpwned.com)
• Avoid Phishing: Verify URLs before entering credentials
• Update Software: Keep OS, browsers, and apps updated
• Use HTTPS: Only enter passwords on secure websites
• Be Careful with Public WiFi: Use VPN when accessing accounts on public networks