Dice roller & coin flip
Roll virtual dice for D&D, board games, and probability demos. Set the number of sides (d20 = 20 sides, d6 = 6) and how many dice to roll — 2d6 means count 2 with 6 sides. The tool shows each die and the total when you roll multiple dice. Switch to coin mode for heads/tails flips. All rolls use your browser’s random source; nothing is stored on a server.
Sides
Count
How to roll dice
1. Choose Dice or Coin mode.
2. For dice: set sides (e.g. 20 for a d20) and count (e.g. 2 for 2d6).
3. Click Roll (or Flip for coins).
4. Read individual results and the sum line when rolling multiple dice.
Dice notation examples
d20 attack roll (D&D)
Set sides to 20, count to 1. One click simulates a single twenty-sided die — the classic “natural 20” roll.
2d6 damage (D&D / board games)
Set sides 6, count 2. You get two results plus their sum — e.g. 4, 5 → sum 9. Average damage for 2d6 is 7 because of the bell-shaped distribution.
Advantage-style double d20
Roll twice with sides 20, count 1 each time, and take the higher result manually — the tool does not auto-pick “best of two” but two quick rolls are enough.
When to use this tool
• When you play tabletop RPGs and need d4, d6, d8, d10, d12, or d20 rolls.
• When you lost physical dice or play online without a VTT.
• When you demonstrate probability (sums of two dice, coin streaks) in class.
When to choose something else
• When you need cryptographically fair rolls for real-money gambling.
• When your game uses specialized dice pools with keep/drop rules — a dedicated VTT may automate that.
• When you need logged, auditable roll history for competitive play.
Tabletop dice notation
Games write rolls as XdY: X = how many dice, Y = sides per die. 3d8 is three eight-sided dice; 1d100 is often simulated with percentile dice or two d10s. This roller maps directly: put Y in “sides” and X in “count”. The sum line answers “how much damage” or “total skill check” when the rules add dice together.
Probability of sums (2d6)
One d6 is uniform: each face 1–6 has probability 1/6. Two d6 summed produce a bell curve centered on 7. There is only one way to get 2 (1+1) but six ways to get 7 (1+6, 2+5, …). That is why many game designers use 2d6 for “average” outcomes with occasional extremes — a concept worth showing in math class.
Coins vs. dice
A fair coin is a d2. Multiple flips model binomial experiments: “how many heads in 10 flips?” Use coin mode for quick yes/no, initiative tie-breakers, or teaching independent trials alongside dice sums.
Frequently asked questions
How do I roll a d20?
Set sides to 20 and count to 1, then click Roll. Each result is between 1 and 20 inclusive.
What does 2d6 mean?
“2d6” is tabletop notation: 2 dice with 6 sides each. Set count 2 and sides 6; the tool lists both rolls and their sum.
What is the average of 2d6?
The mean is 7. Individual sums range from 2 to 12, but 6–8 are most common because many combinations add up to those totals.
Can I roll dice with different sides at once?
This tool rolls identical dice in one batch. For 1d8 + 1d6, roll twice with different side settings.
How random are the rolls?
Uses Math.random() in the browser — fine for games and teaching, not for security or regulated gambling.
Does coin flip show heads and tails?
Yes. Coin mode flips the number of coins you set and labels each as heads or tails.
Is there roll history?
No persistent log — each roll replaces the previous result. Screenshot or note results if you need a record.
Is this free?
Yes, no account needed.