D8 Roller
Roll a d8, 2d8 or up to twenty eight-sided dice at once, with a modifier and the exact odds for every total.
Free · runs in your browser · nothing is uploaded
Recent
Your last 10 settings, saved only in this browser. Nothing is uploaded.
This d8 roller is a free online dice roller for a 8-sided die. It rolls a d8 and gives you one number from 1 to 8, and every face has the same 1 in 8 chance (12.5%). You can roll up to 20 d8 at once, add or subtract a modifier, and roll with advantage or disadvantage. Every die is shown, so you can see which ones were kept, and a table under the result gives the exact odds for the roll you set. A seed or a copied link lets you repeat any roll.
It runs in your browser, so nothing you roll is uploaded. For other dice, use the dice roller or the other single-die pages linked below.
How to use the d8 roller
- Choose a Roll mode. Normal rolls the dice once. Advantage (keep higher) rolls the whole set twice and keeps the higher sum. Disadvantage (keep lower) keeps the lower sum.
- Set the Number of d8 with the stepper, from 1 to 20. One die gives a single roll; two dice give 2d8, and so on.
- Optional: set the Modifier, from −50 to +50, to add a bonus or a penalty to the total, such as the +3 of a damage roll.
- Press Roll again, or change any setting, and the dice roll. A single roll shows a large number with the die beside it. Several dice show every face; with advantage or disadvantage both sets are shown and the dropped one is dimmed.
- Read the Odds panel beside the result. It lists the average, the range, the most likely total and the chance of reaching a target you type in, with a bar for every total.
Recent rolls keeps your last ten results from this visit. Copy link saves your settings and seed in the page address, so a friend can open the same roll.
The stepper and the modifier work together, so a damage roll such as 2d8 + 3 is one setting. Change the numbers as often as you like: each change rolls again and the odds panel updates straight away.
How do you read a d8?
A d8 is an octahedron, two four-sided pyramids joined at the base, with eight triangular faces. It rests on one face, and the number on the top face is your result. Because there is a face on top, a d8 is read the same way as a cube.
What are the odds on a d8?
A single d8 averages 4.5, because each of 1 to 8 has a 12.5% chance. The table shows how the common ways to roll the die compare.
| Roll | Average | Range | Chance of rolling a 8 |
|---|---|---|---|
| 1d8 | 4.5 | 1 to 8 | 12.5% |
| 1d8 with advantage | 5.81 | 1 to 8 | 23.4% |
| 1d8 with disadvantage | 3.19 | 1 to 8 | 1.6% |
Advantage raises the average by 1.31 and disadvantage lowers it by 1.31. A roll of 5 or higher has a 50% chance on one die.
What happens when you roll 2d8?
Two dice no longer give every total the same chance. Totals near the middle can be made in more ways, so they come up more often. 2d8 averages 9, ranges from 2 to 16, and 9 is the most likely total at 12.5%.
| Total of 2d8 | Ways to roll it | Chance |
|---|---|---|
| 2 | 1 in 64 | 1.6% |
| 3 | 2 in 64 | 3.1% |
| 4 | 3 in 64 | 4.7% |
| 5 | 4 in 64 | 6.3% |
| 6 | 5 in 64 | 7.8% |
| 7 | 6 in 64 | 9.4% |
| 8 | 7 in 64 | 10.9% |
| 9 | 8 in 64 | 12.5% |
| 10 | 7 in 64 | 10.9% |
| 11 | 6 in 64 | 9.4% |
| 12 | 5 in 64 | 7.8% |
| 13 | 4 in 64 | 6.3% |
| 14 | 3 in 64 | 4.7% |
| 15 | 2 in 64 | 3.1% |
| 16 | 1 in 64 | 1.6% |
What rolls a d8 in the 5e SRD?
- Longsword, battleaxe, flail, morningstar, rapier, trident, warhammer, war pick, light crossbow, longbow and greatclub all deal 1d8 damage in the SRD 5.2.1 weapon tables, and the quarterstaff and spear deal 1d8 when held in two hands.
- Cure Wounds restores 2d8 hit points plus your spellcasting ability modifier; Sacred Flame, Ray of Frost, Produce Flame and Shocking Grasp each deal 1d8 damage.
- Bard, Cleric, Druid, Monk, Rogue and Warlock use a d8 as their Hit Point Die.
- Bardic Inspiration grows into a d8 at Bard level 5, and Martial Arts grows into a d8 at Monk level 5.
The d8 is the Hit Point Die of the Bard, Cleric, Druid, Monk, Rogue and Warlock. Use the damage calculator to turn these dice into an average damage per hit.
Rules facts on this page come from the System Reference Document 5.2.1 (“SRD 5.2.1”) by Wizards of the Coast LLC, available at https://www.dndbeyond.com/srd. The SRD 5.2.1 is licensed under the Creative Commons Attribution 4.0 International License, available at https://creativecommons.org/licenses/by/4.0/legalcode.
How this tool works and where the numbers come from
Each die is drawn with a seeded random generator so every face from 1 to 8 has the same 1 in 8 chance. Advantage and disadvantage roll the whole set twice and keep the higher or lower sum. The odds are counted exactly by listing every way the dice can fall, not by simulation. Weapon and spell damage comes from the SRD 5.2.1 tables.
Sources
- Wizards of the Coast (2025). SRD 5.2.1, weapons, spells and class features. Licensed CC-BY-4.0 (SRD v5.2.1 (published 2025-05-01); page last updated 2026-03-02) · checked
- Wizards of the Coast (2025). SRD 5.2.1, PDF edition (SRD 5.2.1) · checked
Frequently asked questions
How do you roll a d8 online?
Open this page and the roller has already rolled one d8 for you. Press Roll again for another, or change the number of dice, add a modifier or switch to advantage first.
Is this d8 roller fair?
Yes. Each face from 1 to 8 has the same 1 in 8 chance on every roll, and a roll never depends on the roll before it. The seed only makes a session repeatable: a copied link plays back the same sequence of rolls.
What is the average of a d8?
A single d8 averages 4.5, because each of 1 to 8 has a 12.5% chance. With advantage it averages 5.81 and with disadvantage 3.19.
How do I roll with advantage or disadvantage?
Set Roll mode to Advantage (keep higher) or Disadvantage (keep lower). The roller rolls the whole set twice, shows both, and keeps the higher or lower sum. The note under the result names both sums and the one kept.
How do I roll 2d8?
Set Number of d8 to 2. The result runs from 2 to 16 and 9 is the most likely total, at 8 chances in 64, or 12.5%.
Can I roll several d8 at once?
Yes. Set Number of d8 from 1 to 20. The result shows the sum with the modifier, the lowest and highest die, and the average per die.
Where can I roll other dice?
Use the dice roller for any mix of dice or notation such as 4d6kh3, and the single-die pages for the d4 roller, the d6 roller, the d10 roller, the d100 roller.
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