Dice notation explained
If you’ve seen “roll 3d8+2” in a rulebook and weren’t sure what to do, this guide is for you. Dice notation is a short way of saying how many dice, how many sides, and what to add.
The basic pattern: XdY
- X is how many dice you roll.
- d just means “dice”.
- Y is how many sides each die has.
So 3d8 means “roll three eight-sided dice and add them up.” If X is missing, it’s one: d20 is the same as 1d20.
The standard tabletop set has seven dice: d4, d6, d8, d10, d12, d20 and a second d10 marked in tens (00, 10, 20…) for percentile rolls.
Adding modifiers
A number after a plus or minus is added once, not per die.
- 1d20+5: roll a d20 and add 5. This is how most attack rolls and skill checks look.
- 2d6−1: roll two d6, add them, subtract 1.
You can combine different dice too. A rogue’s sneak attack with a shortsword might be 1d6+2d6+3: the weapon die, the sneak attack dice and the ability modifier.
Advantage and disadvantage
Fifth edition uses advantage when the odds are in your favour: roll two d20s and use the higher one. Disadvantage is the reverse: use the lower one. In notation:
- 2d20kh1: roll 2d20, keep the highest 1.
- 2d20kl1: roll 2d20, keep the lowest 1.
Advantage is worth roughly +3 to +5 on a single roll, depending on the number you need.
Rolling ability scores: 4d6 drop lowest
The most popular way to roll a new character’s abilities is to roll four d6, ignore the lowest die and add the other three. Do that six times. In notation that’s 4d6dl1 (drop lowest 1), and it can also be written 4d6kh3.
This gives scores from 3 to 18, averaging about 12.2, a bit higher than plain 3d6 (average 10.5).
Percentile dice
d% or d100 means a number from 1 to 100. With physical dice, roll the tens die and the ones die together: “30” and “7” is 37, and “00” with “0” is 100.
Exploding dice
Some games, though not standard fifth edition, use exploding dice: when you roll the highest number, roll that die again and add it. The notation is an exclamation mark: 3d6!. It’s a fun house rule for critical hits.
Try it
Every example above works in our dice roller. Type the expression and press Roll. Dropped dice are shown crossed out so you can see exactly what happened.