4d6

4d6 is a dice notation used in gaming to indicate rolling four six-sided dice and summing their face values. Each die has faces numbered 1 through 6, and the four results are added together to produce a single total.

Variant forms exist. The most common use in role-playing games is to generate character abilities by summing all four dice (4d6). A popular alternative, 4d6 drop lowest, discards the smallest result and sums the remaining three dice, producing higher scores on average.

Notation explanation: XdY means roll X dice with Y sides and sum the outcomes. For 4d6, the possible totals range from 4 to 24 when summing all four dice; the expected value is 14 (4 × 3.5).

Drop-lowest variant: the resulting ability scores have a mean around 12.2, with a distribution skewed toward higher values relative to 3d6. The method is standard in several fantasy role-playing games and influences character power and balance.

Probability and distribution: the exact probabilities require combinatorial calculation, but the distribution is unimodal and roughly bell-shaped, concentrated around the middle values. Dice-rolling tools and calculators commonly include 4d6 roll tables.