Roll a D8: Eight Sided Dice Roller
This free d8 roller is for DnD players, Dungeons & Dragons fans and game masters who need a fair eight sided die for weapon damage, spell healing or a class hit die. Tap the die to roll, set how many d8s you want and add a modifier from your ability score or magic weapon. The page covers what a d8 is for in 5e, how it compares with 2d4 and the odds behind each face.
Tap the die to roll 1d8. Space and Enter work too.
Average for 1d8: 4.5 (before you roll)
How to use the d8 roller
Tap to roll. Press the big die to roll. Space and Enter work too once the page has focus, unless you are typing in a box.
Set the count and modifier. One d8 is the default, which matches a longsword or rapier held in one hand. Raise the count when a feature or a higher-level spell adds more d8s, and type your modifier so the total is ready to announce.
Read every face. Several d8s show each face under the total. The average for your current notation appears before you roll, so 1d8+3 previews as 7.5.
For typed notation such as 1d8+3 or a mix with other dice, use the main DnD dice roller. For exact odds, open the dice probability calculator.
What a d8 is used for in 5e
The d8 is a regular octahedron: eight triangular faces. In a standard dice set it sits between the workhorse d6 and the heavier d10, and a lot of mid-damage weapons live here.
One-handed damage on a d8 includes the longsword, battleaxe, rapier, flail, morningstar, warhammer, war pick and greatclub. Ranged options include the longbow and the light crossbow. Some of those melee weapons are versatile, so the same weapon uses a d10 when you put a second hand on it.
A d8 is also the hit die for the bard, cleric, druid, monk, rogue and warlock. When those classes level up or spend hit dice on a short rest, this is the die they roll. The hit points roller can add your Constitution modifier for a level-up roll. Cure Wounds restores 1d8 plus your spellcasting ability modifier, and Sacred Flame deals 1d8 radiant damage at lower levels, with more d8s as the cantrip scales. New to the bag? See what dice you need for DnD.
d8 vs 2d4
A single d8 and two d4s share the same average, 4.5. The spread is different. A d8 can roll any number from 1 through 8 with equal 12.5% odds. Two d4s range from 2 to 8 and bunch nearer 5, and they cannot roll a 1.
That is why a longsword swing feels swingier than a Potion of Healing, even though a potion uses 2d4+2 rather than plain 2d4. If you want to compare other pairs, try both pools in the probability calculator.
Average d8 roll
The average d8 roll on this d8 roller is 4.5. The average of one d8 is 4.5. With a +3 modifier, the average total is 7.5, which is a typical Strength- or Dexterity-based weapon swing after you already hit with a d20. Two d8s average 9; three d8s average 13.5 and have a dedicated 3d8 roller; five d8s average 22.5.
Each face from 1 to 8 has the same 1 in 8 chance. There is no "natural 8" rule in 5e the way a natural 20 matters on an attack roll. A high damage die is just high damage.
More than a d8
Roll the attack on the d20 roller, then come back here for the damage. Other single-die pages cover the d4, d6, d10, d12 and d100. New characters that still need scores can use the stat roller. How rolls stay fair is on the about page and in the FAQ.
d8 roller FAQ
Is this d8 roller free?
Yes. It is free, with no ads and no sign up. Open the page on any device and roll.
What is the average d8 roll?
The average of one d8 is 4.5, which is (1 + 8) divided by 2. Each face has a 1 in 8 chance, or 12.5%. Two d8s average 9.
What is a d8 used for in 5e?
An eight sided die covers longsword, rapier, battleaxe, flail, morningstar and warhammer damage (held in one hand), plus the longbow and light crossbow. It is also the hit die for the bard, cleric, druid, monk, rogue and warlock, and the die for Cure Wounds and Sacred Flame at lower levels.
Is a d8 better than 2d4?
They share the same average of 4.5, but they do not feel the same. A d8 can roll a 1 or an 8. Two d4s range from 2 to 8 and cluster nearer 5, so they are steadier and cannot roll a 1.
Can I roll more than one d8?
Yes. Set the dice count, then tap to roll. You can roll up to 20 d8s here. For mixed dice or typed notation such as 1d8+3, use the main dice roller.
Is the d8 roll truly random?
Each dice roll draws random numbers from your browser's cryptographic generator. Values that would favor a face are thrown out and drawn again, so all eight faces have the same chance.
See the Nat20 Roller FAQ for more on notation, advantage and how rolls stay random.