An online dice roller for board games, D&D and classrooms
Lost the dice, or playing over a video call? This dice roller rolls any combination of d4, d6, d8, d10, d12, d20 and d100 — plus dice with any number of sides you type in — and shows every die, the kept and dropped values, the modifier and the total. Six-sided dice tumble as real 3D cubes; the others flicker through their numbers before landing.
It understands standard tabletop notation, so 3d6+2, 2d20kh1 (advantage), 4d6dl1 (roll four, drop the lowest) and even mixed rolls like 1d8+1d6+3 all work. Every die uses cryptographically secure randomness, nothing is uploaded, and your roll history stays on your device.
How to use the Dice Roller
- Type a roll into Dice notation, or build one: tap a die type (d4 to d100), set the Number of dice, custom Sides and a Modifier, and the notation fills in for you.
- Press Roll (or Enter). The dice animate and settle, and the total appears with a breakdown of every die.
- Use the presets for common tabletop rolls: a d20 check, advantage, disadvantage, ability scores, a fireball’s 8d6, two dice or a percentile roll.
- Dropped dice (from
kh,kl,dhordl) are faded and crossed out so everyone can see what counted. - Press Copy result to paste the roll into a chat, or scroll down to the Roll history of your last 20 rolls.
Dice Roller features
Every standard polyhedral die
d4, d6, d8, d10, d12, d20 and d100 are one tap away, and “Sides” accepts anything from 2 to 1,000 for custom dice.
Full dice notation
Multiple terms, positive and negative modifiers, keep-highest and keep-lowest (advantage and disadvantage) and drop-highest or drop-lowest.
Fair rolls
Each die value comes from crypto.getRandomValues with rejection sampling, so a d20 really does land on every face 5% of the time.
Animated 3D dice
Six-sided dice are real CSS cubes with pips; other dice cycle through their faces and slow to a stop. On devices with a capable graphics chip a WebGL 3D view takes over once you start rolling: every die falls, tumbles and lands on its rolled value. Reduced-motion settings show results instantly.
Dice sounds
A quiet rattle while rolling and a soft chime on the result, with a one-tap mute that is remembered.
History and copy
The last 20 rolls with their notation and breakdown are saved on your device and can be copied in one tap.
Dice notation cheat sheet
Notation is written as NdS: N dice with S sides each. Terms are joined with + or −, and a bare number is a flat modifier.
| Notation | Meaning | Range |
|---|---|---|
1d20 or d20 | One twenty-sided die | 1–20 |
3d6+2 | Three six-sided dice plus 2 | 5–20 |
2d20kh1 | Roll two d20, keep the highest (advantage) | 1–20 |
2d20kl1 | Roll two d20, keep the lowest (disadvantage) | 1–20 |
4d6dl1 | Roll four d6, drop the lowest (ability scores) | 3–18 |
1d8+1d6+3 | Mixed dice with a modifier | 5–17 |
d% or 1d100 | Percentile roll | 1–100 |
Averages and the shape of the odds
The average of one die with S sides is (S + 1) ÷ 2, so a d6 averages 3.5 and a d20 averages 10.5. For N dice, multiply by N: 3d6 averages 10.5 and 8d6 averages 28. A single die is flat — every face is equally likely — but adding dice creates a bell curve. With 2d6 a 7 comes up 1 in 6 times while a 2 or 12 appears only 1 in 36, which is why 7 is the most common roll in many board games.
Advantage changes the odds more than people expect: rolling 2d20 and keeping the highest raises the average from 10.5 to 13.8 and makes a natural 20 almost twice as likely (9.75% instead of 5%). Dropping the lowest of 4d6 lifts the average ability score from 10.5 to about 12.24. For the exact odds of any roll against a target, open the dice probability calculator.
Tips for virtual tabletop play
- Keep the roll history open during a session so disputed rolls can be checked, and copy results into your group chat.
- For damage that mixes dice, type the whole expression once (
2d6+1d8+4) instead of rolling each part separately. - Need a random number that isn’t a die? The Random Number Generator handles any range; for a quick yes or no, flip a coin; to pick a random player, use the Random Name Picker.
Dice Roller FAQ
Is the dice roller random and fair?
Yes. Each die uses the browser’s cryptographically secure random generator with rejection sampling, which removes the small bias a plain modulo would introduce. Every face is equally likely and rolls are independent.
How do I roll with advantage or disadvantage?
Use 2d20kh1 for advantage (keep the highest of two d20) and 2d20kl1 for disadvantage. The Advantage and Disadvantage presets type these for you, and the dropped die is shown crossed out.
Can I roll more than one kind of die at once?
Yes. Join terms with + or −, for example 1d8+2d6+3. The breakdown lists each term separately and the total adds them up with the modifier.
How many dice can I roll?
The builder rolls up to 20 dice, and typed notation allows up to 100 dice in a single roll — enough for the biggest spell damage or a classroom probability experiment.
What does d% mean?
d% is shorthand for a percentile die, d100, which gives a number from 1 to 100. Type d% or 1d100, or press the Percentile preset.
Does it work on a phone?
Yes. The dice, totals and history are laid out for small screens, and the sound can be muted so it does not disturb the table.