Random password generator — cryptographic-grade randomness

Random Password Generator

Generate truly random passwords using cryptographically secure randomness. Unlike basic generators that use predictable algorithms, StrongPassFactory uses crypto.getRandomValues() for genuine unpredictability.

Web Crypto API randomness Zero tracking, zero logging Works fully offline

Random Password Generator

Create a strong secure password in one click. Fully random, fully private.

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Strength
20
Select at least one character type.

What Makes a Password Truly Random?

A truly random password cannot be predicted, guessed, or reproduced — even by the system that generated it. This requires a cryptographically secure pseudo-random number generator (CSPRNG), which draws entropy from your device’s hardware — mouse movements, keystroke timing, network interrupts, and other unpredictable sources. StrongPassFactory’s random password generator uses crypto.getRandomValues(), the same CSPRNG trusted by TLS encryption and banking applications.

The critical difference is between true cryptographic randomness and the pseudo-randomness produced by Math.random(). Math.random() uses a predictable algorithm seeded with a known timestamp. Given enough output samples, an attacker can reconstruct the internal state and predict future outputs. Crypto.getRandomValues() has no such vulnerability.

Understanding Entropy in Random Passwords

Entropy measures the unpredictability of a password, expressed in bits. Each bit of entropy doubles the number of possible passwords an attacker must test. A random password with 80 bits of entropy has 2^80 possible combinations — more than the number of atoms in the universe. Our generator calculates entropy as length x log2(character pool size), giving you real-time feedback.

A 12-character random password using all four character types delivers approximately 79 bits of entropy. A 20-character random password delivers 131 bits. Each additional character multiplies the cracking difficulty by 95. This is why length is the single most important factor in password strength, and why our generator defaults to 20 characters.

Random vs Human-Created Passwords

The difference between a random password and a human-created one is staggering. Humans gravitate toward patterns: dictionary words, keyboard walks (qwerty123), dates, names. Cracking tools exploit these patterns using dictionaries, rule-based mutations, and Markov chains. A 12-character human-created password like “Summer2026!” can be cracked in minutes.

A 12-character truly random password like “L9k#mP2$rV7@” would take centuries to crack. The difference isn’t length or complexity on paper — it’s predictability. Our random password generator eliminates all human bias. Every character is independently selected using cryptographic randomness.

FAQ

Frequently Asked Questions

What is the difference between random and Math.random()?
Math.random() uses a predictable algorithm seeded with a timestamp. Given enough output, an attacker can reconstruct the seed. We use crypto.getRandomValues() from your device’s hardware entropy source.
How long should a random password be?
For most accounts, 16-20 characters. With 20 characters and all types enabled, you get approximately 131 bits of entropy.
Can I get the same random password twice?
The probability is astronomically low — roughly 1 in 95^20. Every generated password is effectively unique.
Should I use a random password for every account?
Yes. Every account needs a unique, randomly generated password. Password reuse is the single biggest security risk.