D&D Dice Roller with 3D Dice
This D&D dice roller rolls any polyhedral dice with 3D animation: tap a quick button for d4 to d100, use Advantage or Disadvantage for a d20 roll, or type notation like 4d6kh3 or 1d20+5. Every roll you make uses your browser’s cryptographic random source, so each face is equally likely.
Roll the dice
How to use the dice roller
- Tap a die button (d4, d6, d8, d10, d12, d20 or d100) for a quick roll.
- Set a modifier, then press Advantage or Disadvantage for a d20 check with two dice.
- For anything else, type notation such as 8d6, 4d6kh3 or 1d20+5, 2d6+3 and press Roll.
- Read each die, the dropped dice and the total, then copy your roll history if you need it later.
Dice notation reference
The notation box reads the same shorthand most GMs already scribble in the margins. Spaces are ignored, and you can roll up to 100 dice of up to 1,000 sides at once.
| Notation | Meaning | Example |
|---|---|---|
| NdS | Roll N dice with S sides (N defaults to 1) | 3d8, d20 |
| d% | Percentile die, same as d100 | d% |
| khN / klN | Keep the highest or lowest N dice | 4d6kh3, 2d20kl1 |
| dhN / dlN | Drop the highest or lowest N dice | 4d6dl1 |
| ! | Exploding dice: a maximum roll adds another die | 3d6! |
| + and − | Add or subtract constants and other dice | 1d8+1d6+3 |
| comma | Roll several groups separately | 1d20+5, 2d6+3 |
| adv / dis | Shortcut for 2d20kh1 / 2d20kl1 | adv+5 |
The comma is the one I use most: an attack and its damage in one press, with two separate totals. Under each result the roller shows the minimum, maximum and average for the expression, so you can sanity-check a homebrew monster’s damage before it hits the table.
How advantage works, in numbers
Advantage in fifth edition means rolling two d20s and keeping the higher. Disadvantage keeps the lower. In notation those are 2d20kh1 and 2d20kl1, and the Advantage and Disadvantage buttons roll exactly that, plus whatever is in the modifier field.
A single d20 averages 10.5. Two d20s keep highest averages 13.825, and keep lowest averages 7.175. So advantage is worth a little over +3 on average, but the effect is uneven. It helps most when you need around an 11, and barely matters when you need a 2 or a 20. Your chance of a natural 20 with advantage is 9.75%, almost double the flat 5%.
The roller only plays the golden natural-20 burst (or the natural-1 crack) when exactly one d20 is kept. With advantage, the burst fires if the kept die shows 20. Roll 3d20 without keeping one and you get no fanfare, because no single die decides the result.
Common rolls cheat-sheet
| Roll | Notation | Average |
|---|---|---|
| One ability score | 4d6kh3 | about 12.24 |
| Attack with advantage, +5 | adv+5 | 18.83 |
| Sneak attack at 5th level | 3d6 | 10.5 |
| Fireball | 8d6 | 28 |
| Longsword crit, +3 | 2d8+3 | 12 |
| Percentile table | d% | 50.5 |
Two notes. A critical hit in 5e doubles the damage dice, not the modifier, so a 1d8+3 hit becomes 2d8+3 on a crit. And 4d6 drop the lowest averages about 12.24 per score, which over six scores lands slightly above the standard array. If your group argues about rolling versus buying stats, the point buy calculator lays out the other side.
Are digital dice fair?
These are. Each die is rolled with crypto.getRandomValues, the same random source browsers use for security keys, and the roller uses rejection sampling: random numbers that would land in an uneven leftover range get thrown away and drawn again. That removes the small bias you get from a naive remainder, so on a d20 every face has exactly a 1 in 20 chance.
Physical dice are a different story. Cheap resin d20s often have air bubbles, rounded edges or uneven faces, and the float test in salt water tends to embarrass a few favourites. That doesn’t mean you should give up your lucky dice. It means a digital roller is a good tiebreaker when someone’s d20 has rolled four natural 1s in a row and the table wants a neutral party.
At the table
Your history stays for the whole session and copies as text, which helps when a player asks what they rolled for initiative three rounds ago. The roller also works with JavaScript turned off: the form submits and the server does the rolling. Pair it with the NPC generator or the tavern name generator and you can improvise most of an evening from one browser tab. The rest of the tools are on the home page.
Frequently asked questions
How do I roll with advantage in D&D 5e?
Roll two d20s and use the higher result. Here you can press the Advantage button or type adv+5 (or 2d20kh1+5) to include your modifier.
What does 4d6kh3 mean?
Roll four six-sided dice and keep the highest three, which is the classic way to roll an ability score. It averages about 12.24, and 4d6dl1 gives the same result.
Is this d20 roller truly random?
It uses crypto.getRandomValues with rejection sampling, so every face of every die is equally likely. No result is weighted or predetermined.
Can I roll attack and damage at the same time?
Yes. Separate the rolls with a comma, for example 1d20+5, 1d8+3, and each group gets its own total.
What are exploding dice?
When a die rolls its highest face, you roll it again and add the new result. Add an exclamation mark after the die, as in 3d6!, to make it explode.