You sit down at your first D&D session and someone hands you a bag of plastic shapes. Pyramids, little jewels, spiky stars. Here is which one is which, what each is for, and the rolls you will make most.
The seven standard dice
A full "polyhedral set" has seven dice. Each is named for how many sides it has: d for die, number for sides.
| Die | Shape | Typical use |
|---|---|---|
| d4 | Pyramid (tetrahedron) | Small weapon damage (dagger), caltrops, minor effects. |
| d6 | Cube | Short sword damage, fireball damage dice, half the stat rolls. |
| d8 | Two pyramids glued (octahedron) | Longsword damage, cure wounds healing. |
| d10 | Kite shape (pentagonal trapezohedron) | Percentile tens digit, bigger weapon damage. |
| d12 | Twelve pentagons (dodecahedron) | Greataxe damage, barbarian rage dice. |
| d20 | Spiky ball (icosahedron) | The headline die. Attack rolls, saving throws, ability checks. |
| d100 | Two d10s or one big d10 | Percentile roll (1-100). Loot tables, wild magic surges. |
The d20 is the main character
Almost every meaningful roll in 5e is a d20. Attack an enemy — roll d20. Try to climb a cliff — roll d20. Dodge a trap — roll d20. You add a modifier (your character's bonus), compare to a target number, succeed or fail. The d20's twenty-sided range means your bonus matters but luck matters more, which is why natural 1s and natural 20s have the drama they do.
Advantage and disadvantage
Roll two d20s and take the higher (advantage) or lower (disadvantage). You will see this constantly. In our dice roller, select d20 and count 2 to simulate it: look at the sum isn't the point, the two individual results are.
Damage rolls: how many dice
Weapon damage is usually one die (1d8 for a longsword, 1d6 for a short sword). Spell damage scales up: fireball is 8d6, meaning roll 8 six-sided dice and add. In the dice roller you can pick d6 and count 8, hit roll, read the sum. For a divine smite you might end up rolling 4d8 — same idea, pick d8 and count 4.
Ability score generation: 4d6 drop lowest
At character creation one method is "4d6 drop lowest" — roll four six-sided dice, discard the smallest, sum the three remaining. Do this six times for your stats. In our tool: pick d6, count 4, hit roll, add the three biggest numbers yourself. Takes about a minute per character.
Percentile (d100)
Two d10s make a d100. One die is the tens digit (00, 10, 20, …, 90) and the other is the ones digit (0-9). Add them for 1-100 (with 00 + 0 counted as 100). The dice roller just gives you a 1-100 result directly — we skip the two-roll ritual.
Which dice do I actually need to buy?
One set covers 95% of play. Experienced players carry multiples of d6 (for big spell damage) and multiple d20s (for advantage rolls without picking up the same die twice). But if you are using our online roller, you have unlimited of every type — just change the count.
What about weird dice?
You will meet d2 (coin flip in disguise), d3 (roll a d6 and halve), d7, d14, d24, d30 and more at some tables. Most modules only ask for the standard seven. If you need an odd range, use our wheel for any number instead.
Try it live
Open the dice roller, pick any die, pick how many, hit roll. The tally on the right tracks how your rolls distribute over time, which is a sneaky way to catch a cursed d20 that keeps rolling 1s.