A browser-based tool that evaluates password strength in real time using entropy estimation, common security rules, and basic attack modeling. Built to demonstrate core concepts in password security and frontend logic.
This project analyzes a user's password as they type and provides immediate feedback on its strength. It combines rule-based checks (length, character diversity) with entropy calculation to estimate how resistant a password is to brute-force and dictionary attacks.
An optional Claude AI integration generates high-level suggestions for improving weak passwords.
- Real-time password strength evaluation
- Entropy-based strength calculation (in bits)
- Estimated time-to-crack using brute-force assumptions
- Detection of common weak passwords (blacklist check)
- Character diversity analysis (lowercase, uppercase, numbers, symbols)
- AI-generated improvement suggestions (via Claude API)
- Minimal, responsive UI
- Password entropy calculation:
log2(character set size) × length - Brute-force vs dictionary attack models
- NIST-style password guidelines (length over complexity)
- Regex-based pattern detection
- Frontend event handling and live feedback systems
- API integration (Anthropic Claude)
This tool is designed for educational purposes only.
It does not guarantee real-world password security and should not be used as a sole measure for protecting sensitive accounts.
- Download or clone the repository
- Open
password_checker.htmlin any modern browser - Start typing a password to see live analysis
Note: AI suggestions require a valid Anthropic API key.
- HTML5
- CSS3
- Vanilla JavaScript
- Claude AI (Anthropic Messages API)
**Mohammad Qaim
2nd Year Computer Science Student
Interest: Cybersecurity, Secure Systems
Location: Islamabad, Pakistan
This project is for educational purposes only.