Is this calculation free and private?

Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.

Password Entropy & Strength Calculator

Calculate password cryptographic Shannon entropy bits, pool character size, and brute-force crack time.

100% free
Private in browser
No signup
No watermarks

Password Length (Characters)

Includes Lowercase (a-z)? (1=Yes, 0=No)

Includes Uppercase (A-Z)? (1=Yes, 0=No)

Includes Digits (0-9)? (1=Yes, 0=No)

Includes Special Symbols (!@#$)? (1=Yes, 0=No)

Entropy (Bits)

105.1

Character Pool Size

Brute Force Time (Log10 Seconds at 10B/sec)

21.6

Rate this tool

Be the first to rate — helps others and improves this page.

About Password Entropy & Strength Calculator

Calculate password cryptographic Shannon entropy bits, pool character size, and brute-force crack time.

How to use Password Entropy & Strength Calculator

Enter your required input values into the fields.
View the automatically calculated results in real time.

Key features

Instant client-side calculation
Real-time updates without page reloads
Private and secure: zero data leaves your browser

Frequently asked questions

Is this calculation free and private?: Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.

Related In-Depth Guides

Learn practical workflows, real-world examples, and expert tips in our comprehensive guides:

Security & DevOps · 5 min read

Password Entropy Explained: How Bits Measure Brute-Force Cracking Time

Understand Shannon entropy in passwords, character pool combinations, and how many seconds, years, or millennia it takes GPUs to crack modern passphrases.