Dice Roller

Roll any dice type — d4, d6, d8, d10, d12, d20, or d100. Roll multiple dice at once and get individual results, total, and roll statistics.

#

Enter your values above to see the results.

Tips & Notes

  • Standard dice types: d4 (tetrahedron), d6 (cube), d8, d10, d12, d20, and d100 (percentile). Each is used for different game situations.
  • In Dungeons & Dragons, the d20 is the most important die. used for ability checks, attack rolls, and saving throws.
  • Use the modifier field to add bonuses or penalties. For example, 1d20+5 represents an attack roll with a +5 proficiency bonus.
  • Rolling multiple dice and summing them (e.g., 3d6) creates a bell-curve distribution. results near the middle are most likely, extremes are rare.
  • The expected average of any die is (sides + 1) / 2. For a d6, that is 3.5; for a d20, it is 10.5.

Common Mistakes

  • Entering 0 or 1 for sides. a die needs at least 2 faces to be valid. Use 4, 6, 8, 10, 12, 20, or 100 for standard dice.
  • Entering negative dice count. you need at least 1 die to roll. The number of dice must be a positive integer.
  • Confusing number of dice with number of sides. "2d6" means 2 dice with 6 sides each, not 2 sides or 6 dice.
  • Ignoring the modifier field when a bonus applies. always include your skill or proficiency bonus for accurate game results.
  • Entering a very large number of rolls. this tool simulates up to 20 rolls at once for readability. For probability analysis, use fewer rolls.

Dice Roller Overview

Dice are probability machines — each roll produces a uniformly distributed random outcome that makes games fair and unpredictable. Understanding dice probabilities helps with game strategy, character building, and appreciating game design choices.

Dice probability formula:

P(result = x on single die) = 1/sides | Average = (1 + sides) / 2 | Range for XdY = X to X×Y
EX: Rolling 2d6: minimum = 2, maximum = 12, average = 7. P(rolling exactly 7) = 6/36 = 16.7% (six ways: 1+6, 2+5, 3+4, 4+3, 5+2, 6+1). P(rolling 10+) = 6/36 = 16.7% (6+4, 5+5, 6+5, 4+6, 5+6, 6+6)
Dice types and statistics:
DieFacesMinMaxAverageCommon Use
d44142.5Small weapons, healing potions
d66163.5Board games, medium damage, stats
d88184.5Medium weapons, ranger dice
d10101105.5Damage, percentile (with d10)
d12121126.5Large weapons, barbarian dice
d202012010.5D&D attacks, saves, checks
d100100110050.5Percentage rolls, wild magic
Probability of rolling at least X on a d20:
Target NumberNormal RollWith AdvantageWith Disadvantage
10+55.0%79.8%30.3%
15+30.0%51.0%9.0%
18+15.0%27.8%2.3%
20 (nat 20)5.0%9.75%0.25%
Understanding dice probabilities takes the mystery out of tabletop game outcomes. When a D&D player needs to roll a 15 or higher on a d20 for a critical check, knowing there is a 30% chance — and that advantage raises it to 51% — transforms abstract chance into a concrete strategic consideration. Game designers use these probability distributions deliberately: a system built around 2d6 produces far more middle results than extremes, creating predictability; a system built around 1d12 is flat and swingy, creating high variance. Knowing which die your game uses shapes how you approach risk.

Frequently Asked Questions

Standard tabletop RPG dice: d4 (4-sided tetrahedron) — used for small weapon damage like daggers; d6 (6-sided cube) — the standard game die, used for everything from board games to character stats; d8 (8-sided octahedron) — medium weapon damage, longbows; d10 (10-sided) — percentile rolls when used as d100, also weapon damage; d12 (12-sided) — large weapon damage, greataxes; d20 (20-sided icosahedron) — the iconic D&D die for attack rolls, saving throws, and skill checks; d100 (two d10s or percentile die) — probability and luck tables. In D&D 5e, most important rolls use the d20.

A fair die gives equal probability to each face. A single d6: each number 1-6 has a 1/6 ≈ 16.7% chance. When rolling multiple dice, probabilities combine — the sums follow a bell curve. Rolling 2d6: you cannot get 1 (impossible), and 7 is most likely (6 ways out of 36 = 16.7%), while 2 and 12 are least likely (1 way each = 2.8%). This is why games designed around 2d6 (like Monopoly, Settlers of Catan) tend toward middle results rather than extremes.

Advantage means rolling 2d20 and keeping the higher result — significantly better odds. Disadvantage means rolling 2d20 and keeping the lower result — significantly worse odds. With advantage, the probability of rolling 15+ increases from 30% to 51%. With disadvantage, it drops to 16%. Advantage/disadvantage cancels out if you have both simultaneously — you just roll 1d20 normally. This mechanic from D&D 5th Edition replaced the old +2/-2 modifier system with a more dramatic swing that feels more impactful to players.

Standard dice notation format: XdY+Z where X = number of dice, Y = sides per die, Z = modifier added to total. "3d6" means roll three 6-sided dice and add results. "2d8+3" means roll two 8-sided dice, add them together, then add 3. "1d20" is just one 20-sided die. "4d6 drop lowest" (common D&D character creation) means roll four d6s and add the three highest results. The total determines the outcome — weapons dealing "2d6+4 slashing damage" produce results between 6 and 16.

Average results for standard dice: d4 = 2.5; d6 = 3.5; d8 = 4.5; d10 = 5.5; d12 = 6.5; d20 = 10.5; d100 = 50.5. Formula: average = (minimum + maximum) / 2 = (1 + sides) / 2. For multiple dice, averages add: 2d6 average = 7; 3d6 average = 10.5; 4d6 drop lowest average ≈ 12.24. These averages matter for game balance — a weapon dealing d8 damage averages 4.5, while d6+2 (average 5.5) is better on average despite the lower die type.

Yes — virtual dice work for any game requiring dice: board games (Monopoly uses 2d6, Risk uses up to 3d6 vs 2d6), card games with dice elements, tabletop RPGs (D&D, Pathfinder, Call of Cthulhu), wargames, probability education, statistics demonstrations, and random number generation for any purpose where you need a fair, transparent random outcome. For tabletop RPGs played remotely or online, virtual dice are widely accepted. Dice rolling apps and websites are standard tools for online play through platforms like Roll20 and Discord.