Dice (singular die[1] or, occasionally, dice[2][3]) are small, throwable objects with marked sides that can rest in multiple positions. They are used in roleplaying games to randomise events and outcomes according to the rules of the games' systems.

Most dice are cubes or other regular polyhedra with each side marked with a unique integer from 1 to the total number of sides. (The numerals 6 and 9, which are reciprocally symmetric through rotation, are distinguished with a dot or underline.) When thrown or rolled, the die comes to rest showing on its upper surface a random integer, each value being equally likely. However, other forms of dice are also common in roleplaying games (see 'Types of dice', below).

Using dice is the most common means of adding chance to a roleplaying game's resolution mechanic (another tool for this is a deck of playing cards), to the extent that games without a random element are often known as "diceless".

Dice notation[]

Dice notation, also called dice algebra, is a common shothand system to represent different combinations of dice and modifiers to be used in dice rolls. In its simplest form, a dice combination is given in the form AdX. A and X are variables, separated by the letter "d", which stands for die or dice. The letter "d" is usually lower-case, but some notation uses upper-case "D" (non-English games can use the equivalent form of the first letter of the given language's word for "dice", but also often use the English "d").

  • A is the number of dice to be rolled (usually omitted if 1).
  • X is usually the number of faces of each die (but could be a different symbol in the cases of less common die types).

For example, if a game would call for a roll of d4 or 1d4 this would mean, "roll one 4-sided die."

If the final number is omitted, it is typically assumed to be a six, but in some contexts, other defaults are used.

3d6 would mean, "roll three six-sided dice." Commonly, these dice are added together, but some systems could direct the player use them in some other way, such as choosing the best die rolled.

To this basic notation, an additive modifier can be appended, yielding expressions of the form AdX+B. The plus is sometimes replaced by a minus sign ("−") to indicate subtraction. B is a number to be added to the sum of the rolls. So, 1d20−10 would indicate a roll of a single 20-sided die with 10 being subtracted from the result. These expressions can also be chained (e.g. 2d6+1d8).

Other forms of notation may be used in specific games if the resolution mechanic is not easily supported by the standard notation. For example, the game Dungeon World uses b[2dX] and w[2dX] to indicate that the best ("b") or worst ("w") of two rolled dice should be used.

Types of dice[]

The single most common type of die (both in roleplaying and beyond) is the d6, a cube with each of its six sides marked with a different number from 1 to 6. (These numbers may be depicted either by a number of dots or by a numeral. Dice other than d6 tend to use numerals.) However, roleplaying games use a wide variety of other types of dice.

Normally, the faces on a die will be placed so every pair of opposite faces will add up to the same number. (This is not possible with 4-sided dice, dice with an odd-number of faces, or dice with non-numerical symbols.)

Standard 7-dice set[]

Because many roleplaying games, most notably Dungeons & Dragons and games derived from it, use a variety of different dice, dice are often sold in sets of seven with matching designs. These seven dice come in six different shapes: five are shaped like the Platonic solids (polyhedra whose faces are regular polygons, i.e. d4, d6, d8, d12 and d20), and the other two dice are pentagonal trapezohedra (10-sided polyhedra whose faces are kite-shaped), one of which is marked with multiples of ten (allowing the pair of 10-sided dice to be combined to generate numbers between 1 and 100).

The dice in the standard set are as follows:

Notation Shape Faces/
d4 Tetrahedron 4 equilateral triangles Unlike other common dice, a four-sided (tetrahedral) die does not have a side that faces upward when it is at rest on a surface, so it must be read in a different way. Each face has three numbers, arranged such that the upright number, placed either near the vertex or near the opposite edge, is the same on all three visible faces. The upright numbers represent the value of the roll.
d6 Cube (hexahedron) 6 squares A common die. The sum of the numbers on opposite faces is 7.
d8 Octahedron 8 equilateral triangles The die resembles two square pyramids attached base-to-base. Usually, the sum of the opposite faces is 9.
d10 Pentagonal trapezohedron 10 kites The die has two sharp corners, where five kites meet, and ten blunter corners, where three kites meet. The ten faces usually bear numbers from zero to nine, rather than one to ten (zero being read as "ten" in many applications). Often all odd-numbered faces converge at one sharp corner, and the even ones at the other. The sum of the numbers on opposite faces is usually 9 (if numbered 0–9) or 11 (if numbered 1–10).

d10s are used extensively in game systems such as Exalted and other games from White Wolf Publishing.

d100 or d% Pentagonal trapezohedron 10 kites A second 10-sided die is included, with faces numbered in multiples of 10 (00, 10, 20, 30 and so on to 90). When rolled with a d10 and added together, this gives an equal chance of every number from 0 to 99. (Depending on the game system, zero is often read as "one hundred".) The notation d100 or d%, or the term "percentile dice", refer to both 10-sided dice together.

The game system Unknown Armies uses percentile dice for its resolution mechanic.

d12 Dodecahedron 12 regular pentagons The sum of the numbers on opposite faces is usually 13.
d20 Icosahedron 20 equilateral triangles The sum of the numbers on opposite faces is 21 if numbered 1–20.

While Dungeons & Dragons uses every type of die in the standard set, the d20 is the main die used for its resolution mechanic (check of success or failure). It is so widely recognised in that context that the d20 System (a generic system derived from Dungeons & Dragons 3rd edition in the year 2000) is named after it, and games derived from D&D or using a d20 resolution mechanic are commonly referred to as "d20 games" whether they use the d20 System or not. The more recent and wholly distinct 2d20 system by Modiphius is also named after the d20 die.

While these forms of the standard dice are the ones most commonly sold in sets, it is also possible to replace certain dice with other shapes with more sides, as long as the number of faces is a multiple of the original (so that the symbols on the faces can be evenly distributed on the new shape). For example, it is common to use a 12-sided die (dodecahedron) with sides numbered 1 to 4 three times as a replacement for the d4, or to use a 20-sided die (icosahedron) with sides numbered 0 to 9 twice as a replacement for a d10. (In these cases, the 12-sided and 20-sided dice are considered to roll better than 4-sided and 10-sided dice.)

Other dice used for roleplaying games[]

  • d2 or coins: Although not strictly dice, flipped coins can be used to generate a random number that is either 0 or 1 (or pick between any other two options).
  • Other polyhedral dice: Some roleplaying games use numbered polyhedral dice other than those in the standard set. For example, Dungeon Crawl Classics uses d3, d5, d7, d14, d16, and d24 as well as the dice in the standard set.[4]
  • Fudge Dice or Fate Dice (dF): As used in the Fudge system, and systems derived from it such as Fate Core, Fudge dice are six-sided dice with two of each of the following sides: + (value of 1), - (value of -1), and blank (value of 0). In Fudge and Fate Core, a dice pool of four such dice are rolled and added together to give a value between -4 and +4. Fate dice and Fudge dice have the same distribution, but differ in construction in that Fudge dice have identical symbols on opposite faces whereas Fate dice have identical symbols on adjacent faces.
  • Roleplaying games published by Fantasy Flight Games often uses custom dice with game-specific symbols. For example, Legend of the Five Rings (5th edition) uses two different dice with four symbols (success, explosive success, opportunity, strife)[5] whereas the Genesys system (based on FFG's older Star Wars RPG systems) has six different dice and six symbols (success, advantage, triumph, failure, threat, despair)[6].
    • Ring Dice from Legend of the Five Rings (5th edition), six-sided dice with the following faces:
      1. blank
      2. success
      3. success and strife
      4. explosive success and strife
      5. opportunity
      6. opportunity and strife
    • Skill Dice from Legend of the Five Rings (5th edition), 12-sided dice with the following faces:
      1. blank
      2. blank
      3. success
      4. success
      5. success and opportunity
      6. success and strife
      7. success and strife
      8. explosive success
      9. explosive success and strife
      10. opportunity
      11. opportunity
      12. opportunity
    • Boost Dice from Genesys are 6-sided dice with the following faces:
      1. blank
      2. blank
      3. success
      4. success and advantage
      5. 2 advantages
      6. advantage
    • Setback Dice from Genesys are 6-sided dice with the following faces:
      1. blank
      2. blank
      3. failure
      4. failure
      5. threat
      6. threat
    • Ability Dice from Genesys are 8-sided dice with the following faces:
      1. blank
      2. success
      3. success
      4. 2 successes
      5. advantage
      6. advantage
      7. success and advantage
      8. 2 advantages
    • Difficulty Dice from Genesys are 8-sided dice with the following faces:
      1. blank
      2. failure
      3. 2 failures
      4. threat
      5. threat
      6. threat
      7. 2 threats
      8. failure and threat
    • Proficiency Dice from Genesys are 12-sided dice with the following faces:
      1. blank
      2. success
      3. success
      4. 2 successes
      5. 2 successes
      6. advantage
      7. success and advantage
      8. success and advantage
      9. success and advantage
      10. 2 advantages
      11. 2 advantages
      12. triumph
    • Challenge Dice from Genesys are 12-sided dice with the following faces:
      1. blank
      2. failure
      3. failure
      4. 2 failures
      5. 2 failures
      6. threat
      7. threat
      8. failure and threat
      9. failure and threat
      10. 2 threats
      11. 2 threats
      12. despair
  • The One Ring uses two types of dice: Success Dice based on standard d6s (numbered 1 to 6, but with the numbers 1, 2 and 3 being unshaded and with a tengwar lambe incorporated in the design of the 6 face) and a 12-sided Feat Die that includes the numbers 1 to 10 as well as an Eye of Sauron (valued 0 and leading to other bad outcomes) and a Cirth (rune) representing G for Gandalf (which leads to automatic success on a roll).

Use of dice[]

Dice are usually used to determine the outcome of events. Games typically determine results either as a total on one or more dice above or below a fixed number, or a certain number of rolls above a certain number on one or more dice (e.g. as part of a dice pool). Due to circumstances or character skill, the initial roll may have a number added to or subtracted from the final result, or have the player roll extra or fewer dice.

See also[]


  1. Dice definition at The Free Dictionary
  2. Dice definition in the Cambridge English Dictionary
  3. Dice definition at Lexico.com, powered by Oxford University
  4. Do you own DCC dice? at RPGnet Forums
  5. Legend of the Five Rings Roleplaying Game at Fantasy Flight Games
  6. Genesys at Fantasy Flight Games

External links[]

  • Dice at Wikipedia, the free encyclopedia.
  • Dice notation at Wikipedia, the free encyclopedia.
  • AnyDice, an online web app for calculating probability distributions