A D3 is a roll with three possible results: 1, 2 or 3. You do not need a special die to make one. Roll a standard D6 and read 1 or 2 as a 1, 3 or 4 as a 2, and 5 or 6 as a 3.
Want to try it? Use the D3 roller below.
That is the whole rule. Most players meet it mid-turn, when something asks for D3 mortal wounds and there is not a single three-sided die anywhere in the pile in front of them. There never was one. Your dice were fine all along.
How to roll a D3 with a D6
Roll one D6 and read across.
| D6 roll | D3 result |
|---|---|
| 1 or 2 | 1 |
| 3 or 4 | 2 |
| 5 or 6 | 3 |
Rulebooks usually word this as "halve the result, rounding up", which is the same instruction written as maths. Roll a 3, halve it to 1.5, round up to 2.
Each result covers two faces out of six, so each has a one in three chance and the average roll is 2. Nothing is lost by generating a D3 this way. It is a genuinely flat distribution, not an approximation.
What 1D3, 2D3 and 3D3 mean
1D3 means roll one D3. 2D3 means roll two of them and add the results together. 3D3 means three, added the same way.
The difference matters more than it looks. A single D3 is flat: 1, 2 and 3 are equally likely. 2D3 gives you anything from 2 to 6, but those results are not equally likely. There is only one combination that makes a 2 and only one that makes a 6, while a 4 can happen three different ways. So if a rule asks for 2D3, expect a 4 more often than either end, and do not treat it as one roll with a wider range.
Why there is no ordinary three-sided die
You cannot enclose a space with three flat faces. Try it with three pieces of card and you end up with an open wedge, not a solid. That is why there is no three-faced equivalent of the cube sitting in your dice tray.
Physical D3s get around it in one of two ways. Most use an ordinary cube with each number printed twice, so the halving is already built into the die. The rest use a rounded or barrel shape that can only come to rest in three valid positions. Both give three fair outcomes. Neither is a solid with three flat faces, because that shape does not exist.
Where D3 rolls show up in your games
D3 rolls tend to appear wherever a game wants a little variation without a big swing. Common uses include:
- A variable number of attacks.
- Variable damage.
- Mortal wounds and similar special damage.
- Healing, or returning models to a unit.
- Random movement.
- Results on a table.
- Quantities generated by an ability or effect.
Warhammer 40,000, Age of Sigmar, The Old World, Kill Team and Necromunda all use D3 rolls somewhere. Exactly which profiles and abilities call for one changes between editions and factions, so treat the list above as the shape of the thing rather than a checklist.
How re-rolls work on a D3
This is the one that causes arguments. Say a rule lets you re-roll results of 1 and you are rolling a D3 for damage. The D6 comes up 2. Do you get the re-roll?
In Warhammer, yes. A 2 on the D6 produces a 1 on the D3, and the D3 is the roll you are actually making. You check the result after halving, not the number printed on the face. That means re-rolling 1s on a D3 triggers on a D6 result of 1 or 2, which is twice as often as it first looks.
That is how Warhammer reads it, not a universal law of dice. Other systems can word it differently, so check the core rules or FAQ for whatever you are playing. The Warhammer 40,000 core rules are free to download if you want the current wording.
The kinds of physical D3 you will find
A cube numbered 1, 1, 2, 2, 3, 3
The most practical physical D3, and the type we make, uses a familiar cube shape numbered 1, 1, 2, 2, 3 and 3. Mathematically it is identical to halving a D6, because that is exactly what it does. The arithmetic has simply moved off your head and onto the die. Ours live in the D3 Three Sided Dice range.
The rounded barrel
A three-sided rod with domed ends that stop it landing on the tips. They roll fairly and they are good fun to own, but they roll like a pencil, they like the floor, and reading them takes a second longer than it should. Fine with one. Less fine with eleven on the table.
Flat triangular tokens
A flat triangle has two faces, not three. It lands face up or face down, so it works as a marker rather than as a true three-outcome die. Worth knowing what you are looking at before you buy one.
Do You Need Dedicated D3 Dice?
No. An ordinary D6 gives exactly the same odds, and anything that claims otherwise is wrong. What a dedicated D3 gives you is speed and a cleaner table. When a weapon does D3 damage across six unsaved wounds, halving six D6s in your head is a small tax you pay every turn. Six dice that already read 1, 2 or 3 remove it.
The other reason is how they look, and that is a perfectly good one. Dice painted to match the army in front of them look like they belong there. There is a D3 roller further up this page, we built it and it works, and we would still rather pick up a die than tap a screen mid-turn. A simulator gives you a number. A die gives you the roll.
Three or four D3s is usually enough for occasional use. If you often resolve several variable results at once, a bigger handful saves you rolling the same die over and over.
Two related oddities while you are here. Scatter and deviation dice answer "where did it land" the way a D3 answers "how much", and you can find them in our Scatter and Deviation Dice range. The rest of the unusual shapes sit together in Special and Extra Dice.
The short version
Roll a D6. 1 or 2 is a 1, 3 or 4 is a 2, 5 or 6 is a 3. You never needed a special die to do it. It is just quicker when you have one.