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Category Security
Entropy: 0 bits (None)
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About

In the era of automated brute-force attacks and rainbow table lookups, the strength of your password is the primary line of defense for digital assets. This Password Generator is designed to create high-entropy credentials that mathematically withstand modern cracking attempts. Unlike human-generated passwords, which often follow predictable patterns (dates, names, common substitutions), this tool utilizes a client-side Cryptographically Secure Pseudo-Random Number Generator (CSPRNG). This ensures that every character or word selected is statistically independent and unpredictable.

The tool offers two distinct methodologies. The Standard Mode generates chaotic strings of characters, maximizing entropy density per character length—ideal for password managers. The Memorable Mode (based on the "Correct Horse Battery Staple" logic) generates passphrases using randomized adjective-noun-number combinations. This method sacrifices a small amount of entropy density for significantly higher recall, making it perfect for master passwords or accounts where you must type the credential manually. All generation happens locally in your browser; no data is ever sent to a server.

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Formulas

The security of a password is measured in Entropy (E), expressed in bits. It represents the number of guesses an attacker would need to make to exhaust all possibilities.

  • Step 1. Determine Pool Size (R). This is the sum of all possible unique items available for each position (e.g., Lowercase + Uppercase + Numbers + Symbols = 94).
  • Step 2. Measure Length (L). The number of characters or words in the password.
  • Step 3. Calculate Entropy. The formula is E = L × log₂(R).
  • Step 4. Permutations. The total number of combinations is RL.

For Memorable passwords, the logic changes slightly. The "Pool Size" becomes the size of the dictionary used (e.g., 4000 words). A passphrase of 3 words has an entropy of roughly 3 × log₂(4000).

Reference Data

Password TypeLengthCharset SizeEntropy (Bits)Est. Crack Time (RTX 4090)
Weak (Numeric)810~26.6Instant
Weak (Alphanumeric)862~47.6< 1 hour
Strong (Random)1294~78.6~3,000 Years
Strong (Random)1694~104.9Trillions of Years
Memorable (3 Words)~20>2000 (Words)~60-70Centuries

Frequently Asked Questions

Humans are terrible at randomness. We tend to substitute 'a' with '@' or 'i' with '1', which hackers anticipate (called 'Leet speak'). A random generator has no bias, making every character equally probable, which maximizes entropy.
It is based on the XKCD concept that length beats complexity. A string like 'Cosmic-Badger-Tumble-42' is easier to remember than 'J8#kL!9z', yet it has sufficient length to make brute-forcing computationally expensive.
Yes, provided the generation is client-side. This tool uses JavaScript's `window.crypto` API to generate values locally on your device. The password is never transmitted over the internet.
For low-risk accounts, 50-60 bits is often sufficient. For banking, crypto wallets, or master passwords, aim for 80+ bits. Anything over 100 bits is considered unbreakable by current computing standards.