Dice

Everyone at the table has a feeling about dice. This draws the actual shape, and the shape is usually narrower than the feeling.

Build a roll and the distribution appears underneath it. One plain die is a flat line, two added together make the familiar hill, and more dice make extreme totals rarer. The spread grows in points but shrinks relative to the average roll. Expected value and spread come along for free, which is how you find out the swingy-feeling roll and the reliable one differ by less than the arguments about them suggest.

Things to try

• Compare 3d6 against 1d20 and see why they feel nothing alike.
• Watch the hill sharpen as you add dice.
• Find how often the tail actually shows up, then decide if it’s worth planning for.
• Check whether that homebrew roll is as swingy as it seems.

Why it’s a speck

Twist the roll, look at the picture.

Open Dice