Dice Roller — Free Online Virtual Dice

How to Use the Dice Roller

1. Set the number of dice: Enter how many dice you want to roll simultaneously in the Number of Dice field. The default is 2, which works for most board games. You can roll anywhere from 1 to 100 dice at once, which is useful for RPG spells that require large handfuls of dice or for probability experiments that need a large sample size.
2. Choose your die type: Select the number of sides per die using the preset buttons for standard polyhedral dice: d4 (tetrahedron), d6 (cube), d8 (octahedron), d10 (pentagonal trapezohedron), d12 (dodecahedron), d20 (icosahedron), and d100 (percentile). If you need a non-standard die, use the Custom Sides field to enter any number from 2 to 100. The selected die type highlights in blue for easy identification.
3. Add a modifier if needed: The Modifier field lets you add or subtract a fixed value from your total roll. Enter a positive number for a bonus (like a strength modifier of +3) or a negative number for a penalty. This value is applied once to the total of all dice, not to each individual die. Leave at 0 if no modifier is needed.
4. Roll and read your results: Press the Roll the Dice button to generate random results. The results panel shows individual die outcomes as circular badges, the total before modifier, the average per die, the highest and lowest individual rolls, the modifier applied, and the final total. A summary line at the bottom shows the complete roll in standard dice notation.

You can roll again at any time by pressing the Roll button. Each press generates a completely new set of random results. Changing the die type via preset buttons also triggers an automatic re-roll for immediate feedback.

How the Dice Roller Works

Variables Explained

• S (Sides): The number of faces on each die. A standard six-sided die has S = 6, meaning each roll produces a random integer from 1 to 6. The theoretical expected value of a single die is (S + 1) / 2, so a d6 averages 3.5 and a d20 averages 10.5 over many rolls.
• N (Number of Dice): How many dice are rolled simultaneously. Each die is rolled independently, meaning the result of one die does not affect any other. Rolling N dice produces N independent random values that are then summed together.
• Modifier (M): A fixed integer added to (or subtracted from) the total after all dice are summed. In RPG notation, a roll of 2d6+3 means N=2, S=6, M=+3. The modifier shifts the entire range of possible outcomes up or down by the specified amount.

Step-by-Step Example

Suppose you roll 3d8+2 (three eight-sided dice with a +2 modifier):

1. Die 1 lands on 5, Die 2 lands on 3, Die 3 lands on 7
2. Total before modifier: 5 + 3 + 7 = 15
3. Apply modifier: 15 + 2 = 17 (final total)
4. Average per die: 15 / 3 = 5.0
5. Highest roll: 7, Lowest roll: 3

The possible range for 3d8+2 is 5 (all ones plus modifier) to 26 (all eights plus modifier), with an expected average of 15.5. Understanding these ranges helps RPG players and game designers evaluate the power level of different dice combinations.

Practical Examples

Example 1: Jake's D&D Attack Roll

Jake is playing a fighter in a Dungeons and Dragons campaign. He attacks an orc with his longsword and needs to roll 1d20+5 for the attack (his proficiency bonus of +3 and Strength modifier of +2 combined). He sets the roller to 1 die, d20, modifier +5, and presses Roll.

• Die result: 14
• Modifier: +5
• Final total: 14 + 5 = 19

The orc's Armor Class is 13, so Jake's attack roll of 19 hits. He then needs to roll damage: 1d8+2 (longsword damage plus Strength modifier). Rolling 1d8 with a +2 modifier, he gets a 6 on the die for a total of 8 damage. The orc takes 8 slashing damage from the successful strike.

Example 2: Rachel's Monopoly Game Night

Rachel is hosting a game night but cannot find her Monopoly dice. She opens the online dice roller and configures it for 2d6 with no modifier, the standard Monopoly setup. Over several turns, she uses the roller to determine her movement around the board.

• Turn 1: Rolls 4 and 3 = 7 (lands on Chance)
• Turn 2: Rolls 6 and 6 = 12 (doubles, rolls again)
• Turn 3: Rolls 2 and 5 = 7 (lands on Community Chest)

The dice roller provides fair, instant results that all players can see simultaneously on Rachel's screen. Since the roller shows individual die values, they can easily spot doubles for the extra turn rule and three consecutive doubles for the jail rule in Monopoly.

Example 3: Professor Chen's Probability Lesson

Professor Chen uses the dice roller to demonstrate the central limit theorem in his statistics class. He first rolls 1d6 ten times and records the results to show a flat distribution. Then he rolls 2d6 ten times to show how the sums cluster around 7.

• 1d6 results: 3, 6, 1, 4, 2, 5, 3, 6, 2, 4 (spread evenly)
• 2d6 results: 8, 7, 5, 9, 6, 7, 11, 8, 7, 6 (clustering around 7)
• Average of 2d6 rolls: 7.4 (close to expected 7.0)

By showing the average and individual roll values, Professor Chen demonstrates that while individual dice are uniformly distributed, the sum of multiple dice follows a bell-shaped distribution. The more dice rolled, the more pronounced this effect becomes, which is a key insight in probability theory.

Example 4: Mia's Yahtzee Tournament

Mia organizes a virtual Yahtzee tournament with friends across different cities. Each player uses the dice roller configured for 5d6 (five six-sided dice). On her first turn, Mia rolls to try for a large straight.

• First roll: 2, 3, 4, 6, 6 (two sixes, close to a straight)
• She keeps 2, 3, 4 and re-rolls 2d6: gets 1, 5
• Final dice: 1, 2, 3, 4, 5 (a large straight for 40 points)

The dice roller's individual die display makes it easy for Mia to identify which dice to keep and which to re-roll. The highest and lowest indicators help players quickly assess their options for different Yahtzee scoring categories like Three of a Kind, Full House, or Chance.

Dice Probability Reference Table

Tips and Complete Guide

Understanding Dice Notation for RPGs

Dice notation is the universal language of tabletop gaming. The standard format NdS+M tells you exactly what to roll: N dice, each with S sides, plus a modifier M. When you see "2d6+3" in a game manual, you know to roll two six-sided dice and add 3 to the total. This notation appears in character sheets, monster stat blocks, spell descriptions, and treasure tables throughout every major RPG system. Mastering this notation lets you set up our dice roller instantly for any game situation you encounter.

Some games extend this notation with special symbols. "4d6 drop lowest" means roll four d6 and remove the smallest result, commonly used for character creation in D&D. While our roller does not automatically drop dice, you can identify the lowest roll from the displayed results and mentally subtract it. The highest and lowest indicators make this straightforward.

Choosing the Right Die for Your Game

Different games require different dice. Classic board games like Monopoly, Backgammon, and Yahtzee use standard d6 dice exclusively. Dungeons and Dragons and Pathfinder use the full set of d4, d6, d8, d10, d12, and d20. Games like Fate/Fudge use special d6 dice with plus, minus, and blank sides, which you can simulate with a d3 mapped to -1, 0, and +1. Warhammer 40,000 primarily uses d6 dice in large quantities, sometimes rolling 20 or more at once for a single attack. Our roller handles all these scenarios by letting you customize both the number and type of dice.

Probability Basics for Better Gaming

Understanding probability makes you a better player and game master. With a single die, every outcome is equally likely: a d20 gives each number a flat 5% chance. But when you add multiple dice together, a bell curve emerges. Rolling 2d6 produces a total of 7 most often (16.67% of the time) because there are six combinations that sum to 7 (1+6, 2+5, 3+4, 4+3, 5+2, 6+1), while totals of 2 or 12 each have only one combination (2.78%). This bell curve effect means multi-dice rolls produce more predictable, consistent results compared to single-die rolls. Game designers leverage this property: damage that uses 2d6 (average 7, range 2-12) is more consistent than 1d12 (average 6.5, range 1-12), even though the ranges are similar.

Using Dice for Decision Making

Beyond gaming, dice are useful for making unbiased random decisions. Need to assign tasks to a team of six people? Roll a d6 to randomly assign each task. Want to generate a random number for a raffle? Use d100 for a percentile result. Teachers use dice to randomly call on students, ensuring everyone gets a fair chance to participate. Our decision maker tool is another great option for random selection from a list of named options.

Common Mistakes to Avoid

• Applying the modifier to each die instead of the total: In standard notation, 3d6+2 means roll three d6 and add 2 to the sum, not add 2 to each die. A correct result of rolling 3, 5, 4 would be 12+2=14, not (3+2)+(5+2)+(4+2)=18.
• Confusing d10 with d100: A single d10 produces numbers from 1 to 10, while d100 (or percentile dice) produces 1 to 100. In physical dice sets, d100 is rolled using two d10s, one for tens and one for ones, but our virtual roller handles this automatically.
• Using the wrong die type for your game: Always check your game manual for the correct dice requirements. Using a d8 instead of a d6 for damage may seem like a small difference, but it shifts your average from 3.5 to 4.5, a 29% increase that unbalances gameplay over time.
• Expecting streaks to self-correct: The gambler's fallacy leads people to believe that after several low rolls, a high roll is due. Each roll is independent. Rolling five 1s in a row does not make a 6 more likely on the next roll. The die has no memory.
• Not accounting for advantage and disadvantage: In D&D 5e, rolling with advantage means rolling 2d20 and taking the higher result, while disadvantage takes the lower. Make two separate 1d20 rolls and compare rather than rolling 2d20 and summing them.

Frequently Asked Questions