Every die from d4 to d100, full RPG notation like 3d6+2, and 4d6-drop-lowest for character stats - rolled with a cryptographic RNG, entirely on your device.
Mass-produced physical dice are rarely perfectly balanced - slight asymmetries make some faces come up more than others, and 20-sided dice are among the worst offenders. This roller uses the browser's cryptographic random number generator (crypto.getRandomValues) with rejection sampling, which means every face genuinely has equal probability - and everything runs on your device, so no server sees or decides your rolls.
Tabletop shorthand: 3d6+2 means roll three six-sided dice, add them up, then add 2. The number before the d is how many dice, the number after is how many sides, and a trailing +/− is a fixed modifier. 4d6L is the classic D&D character-stat method: roll four d6, drop the lowest, sum the best three. Every roll here shows the individual dice, so nothing is hidden in the total.
d4 rolls. The four-sided die is the one people search for most, probably because it is the least common in a dice bag and the most awkward to read. 1d4 is a single d4, 2d4 is two of them added together, and 4d4 is four. Worth knowing that adding dice changes the shape of the odds, not just the range: a single d4 gives 1, 2, 3 and 4 equally often, but 2d4 clusters around 5 and almost never hits 2 or 8. Rolling more dice makes extreme results rarer.
Advantage and disadvantage. Roll 2d20 and take the higher for advantage, or the lower for disadvantage. Both dice are shown here, so you can see what you gave up. Advantage is worth roughly a +4 bonus on average, though the benefit is largest in the middle of the range and shrinks at either extreme.
Stat rolling. 4d6L rolls four six-sided dice and drops the lowest, which is the standard character-creation method and produces a noticeably higher average than 3d6.
Percentile. d100 gives 1 to 100 in one roll, the same as rolling two d10s for tens and units.
Curious about the odds behind the rolls? The standard deviation calculator can show how much a handful of rolls actually spreads. The percentage calculator turns "13 hits out of 20 rolls" into a percentage.