Dice

Dice are polyhedral shapes with numbered sides used to generate random numbers in Dungeons & Dragons. The term polyhedral dice typically refers to dice with more or fewer than six sides.

"Dice" is the plural. The singular of dice is die.

Standard dice

Every edition of Dungeons & Dragons has required the use of 4-sided, 6-sided, 8-sided, 12-sided, and 20-sided dice. Most editions of the game also use 10-sided dice.

With the exception of 10-sided dice, all standard dice used for D&D are platonic solids: a convex polyhedron where all faces are the same shape and size, all angles and sides are equal, and the same number of faces meet at each vertex.

Dice notation

Since Advanced Dungeons & Dragons 1st edition, game rules describing the use of dice have used the 'd' notation. A number after the letter 'd' refers to dice with that many sides. An optional number before the 'd' means to roll that many dice and add the result. The roll may be followed by a bonus or penalty that should be applied.

For example, "d20" refers to twenty-sided dice. A player in D&D 3rd edition might make an attack by rolling 1d20+5 (one twenty-sided die, and add 5 to the result), and his damage with a greatsword might be 2d6+4 (roll two six-sided dice and add 4 to the total).

Individual dice

d2

Not real dice, but a "virtual" method used to generate a number between 1 and 2. The Mentzer Basic set suggested rolling 1d4 and dividing the result by two, while the 5th edition Player's Handbook suggests rolling any die and taking 1 or 2 if the result is odd or even respectively, or if it is in the lower or upper half of the die's values respectively. Dividing a d6 by 3 is common. It's also possible to flip a coin.

Note that there is no such thing as a d1. The D&D 3rd edition rules mention a damage die below d2, but it's simply known as "1".

d3

Another virtual die used to generate a number between 1 and 3. According to the 1983 Basic rules, a six-sided die rolled and divided by two. Alternatively, the numbers 4-6 may be counted as 1-3.

The d3 is typically used for the damage rolls of very weak monsters or spells which players may encounter at first level, or to choose between three random options.

Some manufacturers have since developed actual three-sided dice, but these are uncommon.

d4

A four-sided triangular pyramid-shaped die. All faces are equilateral triangles. The number which appears upright on all three visible faces is the result; for dice with numbers at the corners, this is at the top of all three faces, or for dice with numbers at the edges, this is the bottom of all three faces. The shift from edge-labeled to corner-labeled d4s is believed to have began during the late 1990s.

The d4 is the lowest standard die and is traditionally used for attacks which deal low damage, such as a dagger or the magic missile spell. In many editions of Dungeons & Dragons prior to fourth edition, the wizard class rolled 1d4 at each level for hit points.

Four-sided dice do not roll especially well, and are relatively infrequently used compared to other dice. They are the only standard dice which do not have a flat face at the top. In the roleplaying game community, they are sometimes nicknamed "caltrops" for their pointed tops which the owner might accidentally step on while barefoot.

Four-sided dice used in gaming have been dated as far back as 2,500 BC, where they were used in the ancient Mesopotamian Royal Game of Ur. In 1984, dice maker Lou Zocchi sold an eight-sided d4 marked 1-4 twice which would roll better, but this design did not catch on.

d5

Another "virtual" die created by rolling 1d10 and dividing the result by 2. It is described in the Basic Rules (BECMI), Players Manual (1983), p.12. Most editions of this game do not use this die.

There is no need to create "virtual" dice by halving dice other than the d4, d6 and d10, since half of d8 and d20 are already existing physical dice.

d6

The most common type of dice known outside of tabletop roleplaying games. Six-sided dice are widely used in every edition of Dungeons & Dragons.

Players use multiple six-sided dice to generate a character's ability scores, traditionally three six sided dice added together, although in later editions of the game it became commonplace to roll four six-died dice and discard the lowest roll.

Many spells use multiple six-sided dice added together for their damage, such as Fireball, which in D&D 3rd edition deals 1d6 per caster level in damage. In some editions of the game, a high level spellcaster may need to roll handfuls of dice.

Due to their popularity outside D&D, six-sided dice are easy to buy cheaply in large numbers. Players are generally expected to own more six-sided dice than any other sort, and many game rules rely on this.

d8

Eight-sided dice are shaped like a regular octahedron. They regularly see use for weapon damage, hit dice of certain classes, and certain spells.

d10

The newest of the standard dice, and the only one which is not a regular polyhedron, instead having a spindle shape.

Ten-sided dice are often marked from 0-9 instead of 1-10, on the understanding that a 0 is to be interpreted as a 10. This is occasionally a source of confusion, and is related to a usage where two dice are rolled together to generate the digits of a percentile number from 00 to 99, known as d100 or d% (see below).

d12

A twelve-sided polyhedron, or dodecahedron. The d12 is possibly the dice with the fewest uses, and a player might play every week for a year without ever needing to roll one.

Certain weapons in some editions of the game use the d12, although many numbers in this range simply ask for two six-sided dice (2d6) instead. The barbarian uses the d12 for their hit dice in later editions of the game, with editions of D&D gradually increasing the hit dice of many classes over time; Original D&D, which used the d6 for all hit dice, would have found a d12 hit dice excessive.

The d12 is the highest dice typically used for things like weapon damage, with the d20 reserved for to-hit rolls and the like. The Player's Handbook (3.0) (2000) initially allowed the monk to deal 1d20 damage at high level, but the later D&D 3.5 revised that to 2d10 to preserve the d20's special meaning.

The d12 often trips up new players who mistake it for the more important d20, and thus short-change themselves. It can be identified by its pentagon-shaped (five-sided) faces, whereas the d20 has triangular faces.

d20

The twenty-sided die is an icosahedron, or a regular polygon where all sides are triangular in shape. It is the most important dice used in Dungeons & Dragons, having been used for attack rolls since the earliest editions of the game. D&D 3rd edition's ruleset is named the d20 System for its importance to core gameplay.

The d20 is regularly used for core mechanics such as attack rolls, saving throws, ability checks and skill checks. Prior to D&D third edition, roll-under checks were common, e.g. rolling a d20 and aiming to roll lower than your own Strength score. From third edition onward, the d20 system established a core mechanic of rolling 1d20, adding relevant bonuses, and aiming to meet or exceed a difficulty class set by the Dungeon Master or game rules.

d100

The term d100 or d%, also called percentile dice or percentage dice, is used to refer to a system of generating a number between 1-100 by rolling two ten-sided dice to generate a two-digit number.

Typically, two ten-sided dice are rolled, each numbered from 0 to 9, to generate a two-digit number from 01 to 99, with a roll of 00 interpreted as 100. Dice sets often include a d10 marked from 00 to 90 especially for rolling the tens digit.

Percentile dice are most commonly used to roll on a random table.

Some editions of D&D prior to third edition used the d100 for a system called percentile strength, where fighters with 18 Strength could roll an additional 1d100 to determine how much stronger they were.

It's possible to use more d10s to generate additional digits and roll d1000, d10000 or higher, but this is not standardly used in Dungeons & Dragons.

Unusual dice

Dice manufacturers have produced other unusual sets of dice, including standard-numbered dice in unorthodox shapes, or dice with non-standard numbers of faces which are not typically used in Dungeons & Dragons.

Uncommon form factors

Barrel dice or long dice are prism-shaped and roughly cylindrical, often with tapered ends so that the die can only roll in one direction when thrown and land on one of its faces. Theoretically, fair dice of any odd or even number can be made in this form factor.

The zocchihedron is a spherical hundred-sided die with a patented internal mechanism to stop the sphere.

Computerized dice are sometimes used, such as software using a pseudorandom number generator to simulate the result of rolling dice. Some software allows rolling arbitrary dice which do not normally exist, although this feature is not normally used in Dungeons & Dragons. Digital dice are most often used in online play.

Non-standard numbered dice

Dice with sides other than standard are not used in standard Dungeons & Dragons rules. They can be used in variant rules, to roll on a custom random table, or to play other games.

Dice have been produced of all numbers of faces from 1-sided (a sphere or mobius strip die made as a joke) to 16-sided, as well as 22, 24, 30, 34, 48, 50, 60, and 120-sided dice.

Dice with more than 20 sides are difficult to use as the shape of the die approaches a sphere, increasing the risk that the die will not stop rolling until it falls off the edge of the table.

Benefits of using dice

The presence of polyhedral dice is an iconic feature of tabletop roleplaying games.

According to TSR employee Tim Kask, himself a retired teacher, physical dice are beneficial to many players due to the tactile element, which aids some people in learning.

Many players enjoy collecting dice, a hobby which pre-dates D&D.

History

Origins of polyhedral dice

An ancient icosahedron marked with symbols.

The earliest known dice date back to ancient times. The standard six-sided die marked with pips was already in use in ancient Rome, where it was used for gambling. Even earlier, at least as far back as 3000 BC, the Egyptian board game of senet used two-sided flat sticks to generate random numbers, and it is thought that four-sided ankle bones of animals were used in prehistoric times.

The shapes of the platonic solids, regular polyhedrons of 4, 6, 8, 12 and 20 sides, were known as far back as the time of the Greek philosopher Plato, circa 400 BC. All standard D&D dice are based on these shapes, with the exception of the 10-sided spindle-shaped die. The earliest surviving twenty-sided dice date back perhaps as far as the 2nd century BC, although their use is not known.

Use in modern wargaming

As far back as 1963, twenty-sided dice were used in naval wargaming simulations run by the US Naval War College Museum. These dice were marked from 0 to 9 twice, with two rolled to generate the two digits of a number to roll against a percentage chance of an event.

On Feb 2, 1963, inventor Fredda Sieve patented a game known as Zazz Polyspheres, using polyhedral dice including a twenty-sided die marked 1-20, as well as 12, 8, 6 and 4-sided dice. Sieve had previously patented a dodecahedron-shaped calendar in 1956, which may have served as an inspiration.

Some of the earliest known twenty-sided dice were produced by the Japan Standards Association in the 1960s, who packaged them as "Random Numbers Generating Icosahedron Dice".

Twenty-sided dice marked 0-9 were adopted in a limited capacity by hobby wargamers in the late 1960s and early 1970s. An advertisement in a 1971 issue of Wargamer's Newsletter offered a pair of 20-sided dice for £0.42 (GBP) or $1.20 (USD), sold as percentage dice. They appear to be marked with 0-9 twice. Gary Gygax later included 20-sided dice in his WW2 game Tractics. D&D historian Jon Peterson believes these dice were originally sold in red and black in 1970, and were later imported to the USA by Lou Zocchi.

Gygax acquired a set of polyhedral dice from a company called Creative Publications, who would later supply dice to TSR after the publication of D&D. 20-sided dice of this era appear to have been universally marked 0-9 twice.

Original D&D

Polyhedral dice were required by the original release of Dungeons & Dragons in 1974. Men & Magic (1974) recommended that players own at least pair each of 4-sided, 8-sided, 12-sided and 20-sided dice, and 4 to 20 pairs of 6-sided dice. Uses of polyhedral dice included the d20 for attack rolls and saving throws, a d12 for the confusion spell, 2d8 for turn sticks to snakes, and a d4 to determine the fighter level of elf NPCs.

However, game mechanics overwhelmingly used six-sided dice. Early TSR employee Tim Kask attributes this to the rarity of polyhedral dice, which were not widely used by gamers in 1974. Companies such as Norton Scientific and Edwards sold these dice to the educational and scientific market. Nevertheless, the uniqueness of interesting polyhedral dice and the difficulty of rolling percentile odds with six-sided dice encouraged their use in later sourcebooks.

Many early D&D dice were infamously poor quality, and irregular shape led to poor randomness or bias. More reliable dice were sold by the Japan Standards Association. Lou Zocchi produced precision dice with sharp corners, infamous for denting game boards.

Early twenty-sided dice were numbered from 0-9 twice, rather than 1-20 as with most modern d20s. Gygax recommended coloring in one set of numbers with a crayon in order to read those numbers as ten higher.

10-sided dice were not used by this edition of the game until Supplement II: Blackmoor (1975), which suggested it to generate the level of ixitxachitl NPCs and the random disease chart.

Basic D&D

The Basic Set (Holmes) (1977), p.45 describes the use of 4, 6, 8, 12 and 20-sided dice, while the accompanying adventure module In Search of the Unknown uses the familiar dice terminology in reference to the D20. A set of five dice produced for this set included a white d20 marked 0-9 twice, light blue d12, green d8, orange d6, and yellow d4. They resemble an earlier set believed to be sold by Creative Publications in 1972, except for slight color changes.

The Basic Set (B/X) (1981) uses the dice notation system and additionally describes the d10 and percentage dice. The boxed set included one of each. Players were advised to roll the d4 by spinning it and tossing it straight up, due to its tendency to roll poorly.

The Basic Rules (BECMI) (1983) follows suit and introduces the virtual dice of 1d2 (1d4 divided by two), 1d3 (1d6 divided by two) and 1d5 (1d10 divided by two). Both editions describe the d10 as being marked 0-9 with the 0 read as 10, and with a 00 on percentile dice read as 100. The d4 is described as of the type where the number to be read is on the bottom of the face rather than the top corner.

The Rules Cyclopedia (1991) continued the BECMI approach.

AD&D 1st edition

AD&D 1st edition used the full set of polyhedral dice, including 4, 6, 8, 10, 12, and 20-sided dice. Two 10-sided dice can be used together to roll percentile dice, which will generate a number between 00-99, with 00 read as 100.

All of the polyhedral dice are widely used. For example, the d4, d6, d8, and d10 are used for the hit dice of various character classes. Twenty sided dice are used for attack rolls and saving throws. All dice, except the d20, are needed to roll the damage for various weapons. Percentile dice are used for percentile strength and thief skills.

The "d" dice notation, such as "d6" to mean "one six-sided die" and "2d6" to mean "the total of two six-sided dice", is standardly used in this edition. Some weapon damage rolls deal 1d3 or 1d2 damage.

AD&D 2nd edition

AD&D 2nd edition follows the same standards set by AD&D 1st edition.

D&D 3rd edition

The Player's Handbook (3.5) (2003), p.5 advises that each player requires a set of dice including at least one each of 4-sided, 8-sided, 12-sided and 20-sided dice, two 10-sided dice, and four 6-sided dice.

Some game rules refer to d2 or d3, but these are normally rolled using 6-sided dice.

This edition's mechanical basis was known as the d20 system for the importance of that die to the core gameplay. The d20 is used almost exclusively to determine the chance of success at something, while the other dice are primarily used for spell effects and weapon damage.

D&D 3rd edition exhibits a pattern where certain character classes use the same die as their hit dice for other characteristic abilities: the wizard uses the d4 for Magic Missile and dagger damage, the rogue uses the d6 for sneak attack and shortsword damage, the cleric uses d8 for the mace, and the barbarian uses d12 for greataxe, the chosen weapon of iconic half-orc Krusk.

The Player's Handbook particularly fails to describe how to read a d4, how to "roll" a d2 or d3, or how to read a single d10 marked 0-9, assuming that players will already be familiar with these concepts.

D&D 4th edition

The Player's Handbook (4e) (2008), p.8 describes the standard 4, 6, 8, 10, 12 and 20-sided dice and the standard dice notation, and depicts each of them in photographs.

Fourth edition does not use percentile dice, although it nevertheless describes their use. The special d10 marked 00 to 90 for the tens digit, commonly found in roleplaying game dice sets, is not depicted or described in this book. It describes a d10 marked 1-10, but depicts one marked 0-9, and depicts a corner-marked d4 (unlike earlier editions which explicitly described an edge-marked d4) but does not describe how to read the d4.

Spells in this edition use a broad variety of dice types.

D&D 5th edition

The Player's Handbook (5e) (2014), p.6-7 describes the d4, d6, d8, d10, d12 and d20, as well as the virtual d2 and d3 and percentile dice using d10s marked 0-9. A notable omission is that the rules don't describe how to interpret a d10 marked 0-9, although other game rules in that edition support the traditional interpretation that 0 is read as 10.