A coin has two sides: heads and tails. When you flip it, what are the chances it will come up heads? What are the chances it will come up tails?

Assuming the coin is not tainted, it has an equal chance of coming up on either side. Therefore, it should come up heads one of every two times or 50%. It should also come up tails one of every two times or 50%.

An image of a coin appears near the top left corner of the window. To flip the coin, click on the image. To flip it again, click on it again. The actual and expected results are shown in the bottom half of the window. You can choose to see just results for the current session or to see historical results (since about June 1, 2003). The results are updated after each flip.

To automatically flip the coin multiple times, enter a number in the field to the right of the coin and then click the Auto Flip button. The program automatically performs the number of flips you specified and updates the displayed results. If you enter an especially high number, you might experience some delay as the flips are processed.