🛡️ Password Strength Checker
Free online password strength checker that analyzes your password security in real time. It checks password length, character diversity, matches against common passwords, calculates entropy and brute-force crack time. All analysis happens locally in your browser — your password is never uploaded to any server.
Local Analysis·Privacy Safe·Instant Results🔍 Enter Password
📖 How to Use
Step 1: Enter a Password
Type or paste the password you want to check. Input is hidden by default — click the eye icon to reveal it.
Step 2: Real-time Analysis
The tool instantly analyzes your password across multiple security dimensions including length, character diversity, and structure, updating results as you type.
Step 3: Review Suggestions
Based on the analysis, you'll receive specific improvement suggestions to help you create a stronger password.
🎯 Use Cases
- Account Security Audit: Evaluate the strength of your existing passwords and identify weak ones.
- New Password Validation: Check a new password before setting it to ensure it meets security standards.
- Security Training: Educate users about password security and what makes a password strong.
- Compliance Checks: Verify that passwords meet organizational or industry security policy requirements.
💡 Password Security Knowledge
Entropy is a scientific measure of password strength, measured in "bits". Higher entropy means more randomness and better resistance to guessing. Each additional character adds about 5-6 bits of entropy.
Brute-force cracking attempts every possible character combination to guess a password. A 12+ character mixed password typically takes centuries or millennia to crack via brute force.
Common passwords like "123456", "password", and "qwerty" are extremely easy to crack and should never be used despite their convenience.
❓ FAQ
Is my password sent to a server?
No. All analysis is performed locally in your browser using JavaScript. Your password never leaves your device and is never transmitted over the network.
What entropy value is considered safe?
Generally, entropy over 50 bits is "Strong", over 70 bits is "Very Strong". A 16-character password with all character types has approximately 95 bits of entropy, which is extremely secure.
What is brute-force crack time?
This is an estimate based on current computing capabilities. Actual crack time depends on the attacker's hardware (attempts per second). Our estimate uses a conservative rate of 1 billion attempts per second.