Understanding coin-flip probability

A fair coin has two sides and each flip is independent. That means the chance of heads is 50% every single time.

Independence

Previous flips do not change future flips. Five heads in a row does not make tails more likely on the next flip.

Long-run frequency

Over many flips, the proportion of heads usually gets close to 50%. You can test this in the probability lab.

Try it

Flip a virtual coin and watch the totals update in real time on the coin flip page.