How do I flip a coin online?
Open the page and a flip is already waiting for you, since the tool generates one on load. Press Flip for a fresh toss, and the result reads Heads or Tails along with the running counts. To flip several coins at once, change the number of flips and press Flip again.
Is this coin flip fair?
Yes. Each flip comes from the browser's cryptographically secure random number generator with rejection sampling, so heads and tails are each exactly 50% likely. There is no weighting, no memory of previous flips, and no server that could tilt the outcome.
Can I flip more than one coin at a time?
Yes, up to 100 in a single click. The result lists every flip in order and then totals the heads and tails, which covers a best-of-three, a tiebreak series, or a probability exercise without repeated clicking.
Is the coin flipper free?
Completely. There is no signup, no ad-walled flip limit, and nothing to install. The page is a small piece of JavaScript that runs in your browser tab.
Does it work on a phone?
Yes. The page runs in any mobile browser, so you can flip a coin on a phone without installing an app, and it works offline once the page has loaded.
Is a physical coin flip really 50/50?
Not quite. A team led by Persi Diaconis predicted in 2007 that a flipped coin caught in the hand shows a slight bias toward the side it started on, because the coin precesses about an axis rather than tumbling cleanly. In 2023 a group of researchers tested this by flipping coins 350,757 times and found the same-side rate was 50.8%, matching the prediction. The bias is small but real. A coin flipped here uses a cryptographically secure generator and is exactly even.
I got eight heads in a row. Is that suspicious?
It has a probability of about one in 256, so it is uncommon rather than impossible, and across everyone flipping coins it happens constantly. Streaks are a feature of randomness, not evidence against it: in a sequence of 100 flips you should expect to see a run of six or seven the same somewhere. The sequences that ought to make you suspicious are the ones that alternate too neatly, because that is what humans produce when asked to invent random data.
After five tails, is heads more likely?
No. The coin has no memory, and each flip is drawn independently, so the probability of heads on the next flip is exactly one half regardless of what came before. This is the gambler's fallacy, and it survives because of a confusion with the law of large numbers: over a very long run the proportion does converge toward 50%, but it does so by swamping the early results with sheer volume, not by correcting them. The deviation is never repaid.
Why do 100 flips almost never give exactly 50 heads?
Because exactly 50 is only one of many likely outcomes. The distribution is binomial, with a standard deviation of 5 for 100 flips, so results from 45 to 55 all fall within one standard deviation and are unremarkable. The specific outcome of exactly 50 heads has a probability of about 8%. This surprises people because they conflate the expected value, which is 50, with the most likely single result, which is also 50 but only barely.
Is the flip generated locally?
Yes. Each flip is drawn from your browser's cryptographically secure random number generator, and nothing is transmitted. Nobody, including this site, can see or influence the result.