Password Entropy Calculator — Bits & Crack Time

missing-tools-handlers.generated.ts maps password-entropy-calculator to type proxy and slug password-generator. The missing-tools widget embeds the same React client as /ip-tools/tools/password-generator — Password, Passphrase, and PIN modes with crypto.getRandomValues.

SEO content on this page explains entropy concepts; the interactive UI is the proxied generator with live strength panel, not a separate entropy-only calculator component.

Entropy in bits approximates log2 of the number of equiprobable outcomes. A sixteen-character random password from four character classes can exceed eighty bits — pushing offline crack estimates toward centuries in illustrative models.

password-strength-meter displays explicit entropy bits with character class breakdown. The generator live panel translates entropy into human-readable crack time ranges.

When calculating entropy for a password you already use — not generating new — open password-strength-meter. Type or paste in the input; analysis updates each keystroke with bits, crack time, warnings for qwerty patterns and common lists.

Fully client-side — suitable for drafting master passwords without network exposure.

Both tools assume an illustrative offline attack rate of ten billion guesses per second against unsalted fast hashes. bcrypt, scrypt, and Argon2 slow attacks dramatically — crack time here is educational, not a guarantee for any specific database leak.

Salting and pepper on servers mean rainbow tables defeat naive hash comparisons — see password-hasher page for storage guidance.

Adding length increases entropy linearly in exponent. Adding character classes increases log of charset size. Sixteen random lowercase letters can beat eight mixed characters with predictable pattern.

Use generator length slider to sixteen or more for important accounts; enable all character types in Password mode.

Passphrase mode entropy depends on word list size and word count. Four random words from a large list can exceed thirty bits per word in ideal models — password-strength-meter applies dictionary penalties when phrases match common patterns.

Do not manually pick words — use generator randomness.

Proxy and password-strength-meter never transmit passwords over network after page load. Contrasts with server-side threat tools elsewhere on the site.

Generated passwords exist in page memory until refresh — copy to password manager promptly.

password-leak-checker also proxies password-generator — neither missing slug performs breach database lookup.

Entropy and breach status are orthogonal — high entropy secrets still fail if reused after any site leak.

Export entropy guidance from password-strength-meter screenshots for security awareness slides. Document that client-side calculators supplement — not replace — server-side password policy enforcement at registration.