Password Strength Tester
Test and analyze the strength of any password with entropy calculation and detailed feedback.
The Password Strength Tester is a fast, accurate Security utility designed to test and analyze the strength of any password with entropy calculation and detailed feedback. entirely in your browser with zero server data storage.
All password analysis happens locally in your browser. Your passwords are never sent to any server.
Entropy measures password randomness. Higher entropy = stronger password.
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Systems & Security Engineers • Applied Cryptography & High-Performance Web Tools
How to Use Password Strength Tester
Enter a Password
Type or paste the password you want to test. Use the eye icon to toggle visibility.
View Analysis
See instant feedback including strength score, entropy, and estimated crack time.
Check Character Types
Review which character types (lowercase, uppercase, numbers, special) are included.
Read Suggestions
Get specific recommendations to improve password strength.
Generate Strong Password
Click 'Generate Strong' for a cryptographically secure 16-character password.
Practical Examples & Conversions
password123
Weak - low entropy, common pattern
Related Tools & Converters
Authoritative Standards & Citations
Calculations and algorithms on this page are implemented and verified in strict accordance with the following official technical specifications:
RFC 6238: TOTP: Time-Based One-Time Password Algorithm
Extension of the HMAC-based One-Time Password algorithm HOTP to support time-based moving factors.
NIST Special Publication 800-38D: Galois/Counter Mode (GCM)
Recommendation for block cipher modes of operation: Galois/Counter Mode (GCM) and GMAC.