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The Nature of Randomness
Every tool on this site depends on one deceptively simple thing: a fair random draw. These short guides explain where computer randomness comes from, where it goes wrong, and how to run selections people can trust — no math degree required.
Pseudo-Random vs. True Random: What Your Computer Actually Does
Computers are deterministic machines — so where does randomness come from? PRNGs, entropy sources, and why 'random enough' depends on what you're doing.
Why Math.random() Can't Make Secure Passwords
JavaScript's Math.random() is fast but predictable. What a CSPRNG is, how crypto.getRandomValues works, and why it matters for passwords.
The Fisher–Yates Shuffle — and Why Naive Shuffles Are Biased
Sorting by a random comparator looks random but isn't. How the Fisher–Yates algorithm produces every ordering with equal probability.
How to Run a Fair Raffle or Lottery Draw
Uniform probability, transparency, and auditability: a practical checklist for running draws people can trust, online or off.