Password strength calculator (entropy)
Estimate password entropy (bits) and crack time from length and character types.
Entropy
71 bits
RatingStrong
Character pool62
Crack time (fast attack)5,112 years
Theoretical estimate (10 billion guesses/s). Use a password manager and long, unique passwords.
How the calculation works
Entropy measures unpredictability: entropy = length × log₂(pool size). Each extra bit doubles the guessing effort.
Frequently asked questions
What boosts strength the most?
Length. A longer password beats complex character substitutions.
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Updated on June 18, 2026 · by Rafael Rossi · Methodology & sources