Password Strength Checker
Estimate password strength and entropy without sending it anywhere. Free, private and instant.
About the Password Strength Checker
Password strength depends mostly on length and unpredictability. Entropy in bits estimates how many guesses an attacker would need.
When to use it
Use it to compare options quickly. The estimate cannot spot common words or leaked passwords, so unique random passwords are still best.
How to use the Password Strength Checker
- Enter or paste your input in the fields above.
- The result updates as you type, or press Run.
- Press Copy to copy the output.
Frequently asked questions
Is the Password Strength Checker free?
Yes. It is completely free, with no signup and no usage limits.
Is my data uploaded anywhere?
No. Everything runs locally in your browser, so what you type never leaves your device.
Does the Password Strength Checker work on mobile?
Yes. The tool is responsive and works on phones, tablets and desktops.
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