Password Generator
Generate cryptographically secure passwords and passphrases with custom character sets and entropy scoring.
Password Generator
CSPRNG Web Crypto security with Shannon entropy calculation.
⚙️ Security Settings
Educational Purpose Disclaimer
This calculator is provided for informational and educational estimation purposes only. All calculations and projections are based on standard mathematical formulas and assumed inputs. The output values should not be considered professional financial, legal, tax, or medical advice. ProCalc is not a registered financial advisor or licensed practitioner. Always consult a qualified professional (such as a Chartered Accountant, certified planner, or physician) before making major decisions.
What is the Password Generator?
The Password Generator is a high-security, browser-only tool for generating strong, uncrackable passwords and memorable passphrases. Weak, reused, or predictable passwords remain the #1 vector for data breaches and account takeovers.
Our tool uses the browser's native Web Crypto API (`window.crypto.getRandomValues`) to generate true cryptographically secure pseudorandom numbers (CSPRNG). It calculates exact Shannon Entropy ($H = L \log_2 N$) in bits to give you a mathematically rigorous score of how hard your password is to brute-force.
Key Features
- CSPRNG Security: Zero weak `Math.random()` usage. All randomness is derived from OS hardware entropy.
- Custom Character Sets: Toggle Uppercase (`A-Z`), Lowercase (`a-z`), Digits (`0-9`), Special Symbols (`!@#$%^&*`), and Exclude Similar Characters (`i, l, 1, O, 0`).
- Memorable Passphrase Mode: Generate readable multi-word passphrases (e.g. `correct-horse-battery-staple`) using an EFF-inspired wordlist.
- Real-Time Entropy Meter: Displays entropy in bits ($H$) and estimated time to crack at 100 billion guesses per second.
- Bulk Generator: Generate up to 50 secure passwords at once.
- 100% Private: Passwords are generated strictly inside client-side RAM and never transmitted anywhere.
How Does the Password Generator Work?
1. Choose Type: Select Random Password or Memorable Passphrase mode.
2. Set Length: Adjust password length slider (8 to 128 characters).
3. Select Character Sets: Toggle uppercase, lowercase, numbers, and special symbols.
4. Check Strength Meter: Ensure entropy is above 60+ bits (Strong) or 80+ bits (Very Strong).
5. Copy Securely: Click Copy to Clipboard. Password is cleared from memory when tab closes.
Formula & Calculation Method
Shannon Entropy Formula:
$$H = L \times \log_2(N)$$
Where:
- $L$ = Password length (number of characters)
- $N$ = Pool size of available character set
- Lowercase ($a-z$): $N = 26$
- Lower + Upper ($a-z, A-Z$): $N = 52$
- Alpha + Numbers ($a-z, A-Z, 0-9$): $N = 62$
- Full Set (+ Symbols): $N = 94$
Time to Crack (Brute Force at $10^{11}$ guesses/sec):
$$\text{Seconds} = \frac{2^{H-1}}{10^{11}}$$
Example Calculation
Password: `k9#mP2$xL8!vQ4#w` (Length 16, Full Set $N=94$)
- Entropy: $16 \times \log_2(94) = 16 \times 6.5546 = 104.8 \text{ bits}$
- Strength Tier: Very Strong (Military/Enterprise Grade)
- Time to Crack: ~34 trillion years at 100 billion guesses/sec
Frequently Asked Questions
**Shannon Entropy Formula:** $$H = L \times \log_2(N)$$ Where: - $L$ = Password length (number of characters) - $N$ = Pool size of available character set - Lowercase ($a-z$): $N = 26$ - Lower + Upper ($a-z, A-Z$): $N = 52$ - Alpha + Numbers ($a-z, A-Z, 0-9$): $N = 62$ - Full Set (+ Symbols): $N = 94$ **Time to Crack (Brute Force at $10^{11}$ guesses/sec):** $$\text{Seconds} = \frac{2^{H-1}}{10^{11}}$$
Disclaimer: This tool is provided for informational and calculation purposes. Output values are estimates based on standard user inputs.