Password Strength Checker
This Password Strength turns the figures for password Strength into a result you can review. Keep the inputs, units and time period consistent.
Strength
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Entropy—
Length—
Est. time to crack—
Runs in your browser. Nothing is sent or saved.
✉ Email me this result
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How it works
Entropy ≈ length × log2(character set size)How to use the Password Strength
Enter the requested values and start with one realistic example. Read the result together with its unit or label, then change one input at a time if you want to compare options.
Review the assumptions on the page and confirm any result that affects money, safety, technical work or another important decision.
Frequently Asked Questions
Is my password sent anywhere?
No. The check runs entirely in your browser using JavaScript. Nothing is uploaded or stored.
How is crack time estimated?
It assumes a fast offline attacker trying about 10 billion guesses per second. Real-world times vary widely, so treat it as a rough guide.
Can I use the result as an exact answer?
Treat it as an estimate or check unless the page and the rules that apply to you confirm otherwise. Rounding, fees and personal details can change the final result.