Password Strength Checker
Test the security of your password offline. Analyzes entropy, complexity, and estimated time to crack. 100% private — your password never leaves your browser.
Enter a password
0 bits
Entropy
Instant
Time to Crack
At least 12 characters
Contains uppercase letter
Contains lowercase letter
Contains number
Contains symbol
Frequently Asked Questions
Is it safe to type my real passwords into this strength checker? ▼
Yes. The tool runs 100% client-side in your browser using local JavaScript. No keystrokes, password strings, or analytical data are transmitted over the internet, logged in cookies, or sent to backend servers.
How is the estimated crack time calculated? ▼
The estimated crack time is computed by calculating the total mathematical search space (character pool size raised to the power of password length) and dividing that by a simulated high-speed GPU hash-cracking rate, providing realistic estimates ranging from instant to centuries.
Why does the tool check for multiple character sets? ▼
Mixing uppercase, lowercase, numbers, and symbols expands the character pool size from 26 up to 94 possible characters. Expanding the pool significantly multiplies the entropy per character, drastically raising the work factor required for brute-force attacks.
What is considered a strong entropy score in bits? ▼
Generally, passwords with an entropy score of 60 to 79 bits are considered moderately secure against online attacks, while passwords with 80 bits or higher provide robust defense against modern offline brute-force and dictionary attacks.
Does the strength checker save my test history or cache passwords? ▼
No. Passwords evaluated by this tool exist only in temporary browser RAM while the page is open. Refreshing or closing the tab immediately purges all input data from memory.