Password
abcd
Summary
Weak / very low entropy / quickly enumerable in theory
Encoding & Decoding
Password Strength Tester — Entropy and Crack-Time Estimate
Estimate password entropy, character-pool size, and theoretical offline crack time from length and character classes, with improvement suggestions. Evaluation runs entirely in the browser; passwords are not uploaded. Results are theoretical heuristics, not a guarantee of real-world security.
PasswordSecurityEntropy
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编码加解码
Password Strength Tester
EMPTY
Cracked in: Instant
Entropy: 0 bits
输入密码后显示改进建议；结果不包含原文密码。
Length 0
Numbers (0-9) 123
Mix Case (Aa) aA
Symbols (!@#) !@#
Use cases
- Sanity-check whether a candidate password looks too weak
- Compare how character-class choices change estimated strength
- Do a quick local review before writing credentials into production configs
How to use
- Enter the password to evaluate
- Review score, entropy, and estimated crack time
- Adjust length or character classes based on the suggestions
Example input and output
FAQ
Does the estimate equal real-world security?
No. It models theoretical search space from length and character classes. It does not check breach corpora or predictable patterns—treat it as guidance only.
Is the password uploaded?
No. Evaluation stays in the browser.
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