A/B Testing Password Strength Calculator FAQ
Answers to common questions about comparing password designs, estimated entropy, inputs, and result limitations.
This FAQ explains what the calculator compares, how to use its inputs safely, and why its estimates should be treated as educational comparisons rather than guarantees.
General questions
Basic information about what the calculator does and does not do.
What does the A/B Testing Password Strength Calculator compare?
It compares two proposed password designs using estimated effective entropy based on length, character variety, and predictability.
Should I enter my actual password?
No. Enter only non-sensitive details such as length, character types, and an estimated predictability penalty.
Does a higher result mean a password is guaranteed secure?
No. A higher result indicates a larger estimated search space in this model, not guaranteed protection.
Can I use this calculator for passphrase-style designs?
You can compare their length and estimated predictability, but familiar phrases may deserve a larger penalty.
Inputs and calculation
How each input affects the entropy estimate.
How is password length used?
Length is multiplied by the selected estimated bits per character before the penalty is applied.
What does character variety mean?
It is the selected category of characters used by the design, represented by an estimated bits-per-character value.
What is the predictability penalty?
It is a percentage reduction for content that may be easier to guess, such as words, dates, patterns, or personal references.
What does the estimated entropy difference show?
It shows Password B's estimate minus Password A's estimate. Positive values favor B.
How is relative strength change calculated?
It divides the entropy difference by Password A's estimated entropy and expresses the result as a percentage.
Accuracy and security context
Important boundaries around the estimate.
Why is the result only an estimate?
The calculator does not examine the actual password or model every real-world attack method.
Does adding symbols always provide a large benefit?
Symbols increase the selected character-pool estimate, but predictable placement or familiar substitutions can reduce the practical benefit.
Does the calculator check breached passwords?
No. It does not check password databases, exposure lists, or any password text.
Does password uniqueness matter if the entropy estimate is high?
Yes. Reuse can expose multiple accounts if one credential is stolen or disclosed.
Does multi-factor authentication affect the entropy result?
No. It is not part of this formula, though it can add a separate account-protection layer where available.
Using comparison results
How to interpret A/B outcomes responsibly.
What should I do if Password B has a positive difference?
It means B has the higher estimate under the inputs chosen. Review whether the input assumptions, especially the penalties, are realistic.
What if Password A has the higher result?
A negative B-minus-A difference means A has the higher estimated entropy in the comparison.
Can two designs have the same estimated entropy?
Yes. Different combinations of length, variety, and penalty can produce similar adjusted estimates.
What is a sensible penalty for a random design?
The calculator leaves that judgment to the user. A design with less familiar structure generally warrants a lower penalty than one based on recognizable information.
Should I enter my actual password?
No. Enter only non-sensitive details such as length, character types, and an estimated predictability penalty.
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