Coin flip guide
Coin flip probability explained
A fair coin has two equally likely sides. That simple setup leads to useful patterns once you start repeating flips.
One flip, two equal outcomes
For a fair coin, heads has probability one half and tails has probability one half. Each new flip begins with the same odds, regardless of what happened before.
Repeated flips
Sequences grow quickly: two heads in a row has a one-in-four chance, while three heads in a row has a one-in-eight chance. These results are less common, not impossible.