To roll a dice using this tool, enter an expression in the text field above. You can do this by typing, or clicking the dice and notation buttons. Every dice expression is a sum of terms, which include flat numbers (e.g., a modifier like +3), an amount of polyhedral dice (e.g., 1d4 or 8d6), standard mathematical symbols (e.g., + or -), and additional notation.
Additional notation allows you to roll more complex dice strings, such as rerolling dice below a given number or taking the best outcome from a number of rolls. You can use the following notation at the die-level or expression-level.
Die-level notation should be directly after a single dice term:
khn — keep highest n. 4d6kh3 rolls four d6s and keeps the best three (the classic D&D stat-array roll).kln — keep lowest n. The mirror of kh. 2d20kl1 rolls two d20s and keeps the worst one.rn — reroll once on values ≤ n. 1d6r2 rolls a d6; if it lands on 1 or 2, reroll once and keep whatever comes up (including another 1 or 2).
Expression-level modifiers wrap the whole expression in parentheses:
adv(expr) — advantage. Roll the whole expression twice, take the higher total.dis(expr) — disadvantage. Roll twice, take the lower total.
If you use the dice and notation buttons, this tool will group die terms if they are identical to the last term in the string (i.e., clicking the d6 four times adds 4d6 to the text field), add die-level notation will apply to the last term in the string, and expression-level notation will wrap the entire string.