Dice roller

How to roll dice online

1. Tap a die: d4, d6, d8, d10, d12, d20 or d100. Set How many first to throw several of the same die (3 and d6 rolls 3d6).
2. For a d20 with advantage or disadvantage, pick it next to d20, then tap d20. Two dice are thrown and the one that does not count is struck through.
3. For anything else, type the roll into Any roll and press Roll or Enter: 2d6+3, 4d6kh3, 1d8+2d6+4, 1d20-1.
4. Read the total and every die beneath it. Dice that count have a solid edge; dropped dice are faded and struck through.
5. To keep a roll you use often, type a name such as Longsword under Saved rolls and tap Save. It becomes a button that rolls it in one tap.

Dice notation this roller reads

• NdM: N dice with M sides. 3d6 is three six-sided dice; d20 on its own is one. d% is a d100 (1 to 100).
• +N and -N: add or take away a fixed number. 1d20+5 gives 6 to 25.
• khN / klN: keep the N highest or N lowest dice. 4d6kh3 keeps the best three of four; 2d20kl1 keeps the lower of two.
• dlN / dhN: drop the N lowest or N highest. 4d6dl1 is the same roll as 4d6kh3. Without a number, one die is kept or dropped.
• Several parts joined with + or -: 1d8+2d6+4, 2d6-1d4. Up to 20 parts and 1,000 dice in one roll, with up to 1,000 sides per die.

A roll that cannot be thrown is refused with the reason rather than guessed at: 0d6 rolls no dice, 1d0 is a die with no sides, 1001d6 is over the 1,000-dice limit, and 4d6kh5 keeps more dice than it rolls. While you type, the line under the box shows the lowest and highest total the roll can give.

What the numbers mean in practice

Adding dice changes the shape of the odds, not just the size. One d12 gives every number from 1 to 12 the same chance. 2d6 also tops out at 12, but its totals bunch in the middle: 7 comes up on 6 of the 36 ways two dice can land (16.7 %), while 2 and 12 each need one exact pair (1 in 36, 2.8 %).

Advantage on a d20 lifts the average from 10.5 to about 13.8, and the chance of rolling 11 or more from 50 % to 75 %. A natural 20 goes from 5 % to 9.75 %. Disadvantage mirrors it: the average drops to about 7.2 and 11 or more becomes 25 %. Worked example: you need 15 or more. A plain d20 makes it 6 times in 20 (30 %); with advantage you miss only when both dice show 14 or less, 0.7 × 0.7 = 49 %, so you succeed 51 % of the time.

4d6 drop the lowest averages about 12.24 per score, against 10.5 for a plain 3d6, and it makes very low scores rare: a total of 3 needs all four dice to show 1, 1 in 1,296.

What it cannot do

• No shared table between players: each person rolls on their own screen and nobody else sees the result. Show your screen, or read the result out, when the group needs to see it.
• No 3D dice physics. The short animation is decoration; the number is drawn first and the dice do not bounce or tumble.
• Saved rolls stay on this device, in this browser. They do not follow you to your phone or another browser, and clearing site data removes them.
• No exploding dice, rerolls, success counting or other system-specific rules; only keep, drop and plus or minus.
• Up to 1,000 dice and 1,000 sides per die in one roll. Past 100 dice in one part, the dice are summed but not all shown one by one.

Privacy and what is stored

Rolls happen in this page; nothing you type is sent anywhere. The page sends an anonymous page-view count and, on your first roll, the fixed word dice-roll; never a roll, a name or a result. Saved rolls are kept in this browser's storage until you tap Clear saved rolls. The history lives only in this tab and is gone when you close it.

Questions

How do I roll a dice from 1 to 6?

Tap d6. Each face from 1 to 6 comes up with the same chance, 1 in 6. Set How many to 2 or 3 first to roll several six-sided dice at once and see each die and the total.

Is an online dice roller really random?

This one uses crypto.getRandomValues, the cryptographic random generator built into your browser, and rejection sampling, so every face of every die has exactly the same chance. The result is fixed before the short animation starts, and the animation cannot change it. Streaks still happen: with a d20, the same number twice in a row comes up once every 20 rolls on average.

How do I roll with advantage or disadvantage?

Switch the d20 setting to Advantage or Disadvantage and tap d20. The roller throws two d20s and keeps the higher (advantage) or the lower (disadvantage); the other die is shown struck through. Typed out, that is 2d20kh1 and 2d20kl1, so 2d20kh1+5 adds a modifier.

How do I roll 4d6 and drop the lowest?

Type 4d6kh3 (keep the highest three) or 4d6dl1 (drop the lowest one); both mean the same. All four dice are shown and the dropped one is struck through. The total averages about 12.24, against 10.5 for a plain 3d6. For six ability scores, save it as a button and tap it six times; the history keeps all six totals.

Can I use it for board games and tabletop games?

Yes. Tap the die the game asks for, set How many for games that roll several, or type the roll a rulebook gives, such as 2d6 or 1d8+2d6+4. Save the rolls you make often as buttons with a name, such as Longsword 1d8+3; they stay on this device.

What does 2d6+3 mean?

Roll two six-sided dice and add 3. The number before the d is how many dice, the number after it is how many sides each has, and +3 or -1 is added to the total. 2d6+3 gives 5 to 15, and 10 is the most likely total.