Type it exactly as you would after /roll in Foundry's chat. In Foundry itself, add # a label at the end to describe the roll, or wrap a formula in [[ ]] inside a journal or chat message to make an inline roll.
Exact Odds
Worked out from every way the dice can land, not by simulation. Exploding dice can in theory go on forever, so the tester follows each explosion 40 times; what it leaves out is far too small to change any number shown.
| Result | Exactly | At least | Chart |
|---|
What the Tester Understands
These are the core Foundry dice terms and modifiers. Game systems and modules can add their own (a system's ability scores, for example, written as @abilities.str.mod), and the tester doesn't know your character, so replace those with plain numbers.
| Write | Meaning | Example |
|---|---|---|
NdM | Roll N dice with M sides and add them up | 3d6 |
+ − | Add or subtract dice terms and plain numbers | 2d6+1d4-1 |
kh kl | Keep the highest or lowest dice (one, unless you give a number) | 2d20kh, 4d6kh3 |
dl dh | Drop the lowest or highest dice | 4d6dl |
r rr | Reroll matching dice once, or keep rerolling until they stop matching | 1d20r1, 1d20rr<3 |
x xo | Explode: roll another die when a die shows its maximum (or matches what you give), again and again, or only once | 1d10x, 2d6xo |
min max | Treat any die below (or above) a number as that number | 3d6min2 |
cs | Count successes: how many dice match, instead of adding them up | 6d10cs>=6 |
df | With cs: subtract one for each die that matches a failure | 5d10cs>=6df=1 |
dF | Fate dice, each −1, 0 or +1 | 4df |
Comparisons are written =, >, >=, < or <= followed by a number; a bare number means "equal to". Foundry also supports multiplication, division, parentheses, dice pools in braces and coin flips; the tester leaves those out. For percentile rolls, write 1d100.
Where to Go Next
- Macros & Automation: Put a formula you trust behind a button on the hotbar.
- Journals & Handouts: Inline rolls inside journal pages.
- Playing Solo in Foundry: Roll tables and formulas as a solo oracle.