How the flip works
Every flip reads a single random bit from crypto.getRandomValues, the browser's cryptographically secure random number generator, and maps 0 to tails and 1 to heads. Unlike a real coin — which physics research has shown is very slightly biased toward the side facing up when it is flipped — this digital coin is exactly 50/50. There is no wobble, no weighting, and no way to influence the outcome, which makes it ideal for settling disputes fairly.
Why flip many at once
Flipping ten or a hundred coins in one click is more than a novelty. It is a live demonstration of two core ideas in probability. The law of large numbers says that as you flip more coins, the observed percentage of heads gets closer to the true 50% — you will see the tally drift toward even as the count climbs into the hundreds. At the same time, short runs of five or six heads in a row are completely normal, which is a great illustration of why streaks do not mean the coin is “due” for the other side.
Using the running tally
The tool keeps a cumulative count of heads and tails across every flip in your session, along with each side's percentage. That lets you run your own little experiment: flip a hundred, note how far the split is from 50/50, flip another hundred, and watch it tighten. The Reset button clears the tally whenever you want a fresh start — useful if you are using the coin to make a series of independent yes/no decisions and do not want the old counts cluttering the view.
Common uses
A coin flip is the classic tie-breaker: who goes first, which restaurant, which of two equally good options. It is also a legitimate decision-making trick — assigning heads and tails to two choices and flipping often reveals your true preference in the instant before the coin lands, when you catch yourself hoping for one result. For teachers, it is a zero-setup probability lab. For anyone, it is a fair referee that cannot be accused of taking sides.
Privacy notes
The coin runs entirely in your browser. No flip, tally, or result is sent to a server or saved, so your decisions stay private and the randomness cannot be manipulated by anyone. Because you can inspect that it runs locally, it is more trustworthy for a genuinely fair flip than a server you cannot see.