Dice Roller

Roll dice online

Choose how many dice, which die, and an optional modifier. The large number is your total; the line underneath shows every individual die and the arithmetic. Press the refresh button to roll again.

Everything happens in your browser. Nothing is uploaded, stored or logged, and no roll is ever written into the page address — a result restored from a link would not be a roll.

The standard dice

Seven dice cover almost every tabletop game:

d4 · d6 · d8 · d10 · d12 · d20 · d100

The d6 is the ordinary cube from board games. The d20 is the workhorse of most role-playing systems. The d4, d8, d12 and d10 fill out the polyhedral set, and the d100 — often called percentile — covers rolls expressed as a percentage chance.

A d100 here is one draw from 1 to 100. Rolling two ten-sided dice, one for tens and one for units, produces exactly the same distribution, so nothing is lost by doing it in a single step.

Reading dice notation

Games write rolls in a compact form: 4d6+2 means roll four six-sided dice, add them together, then add 2. To make that roll here, set How many to 4, choose d6, and enter 2 as the modifier.

The modifier is applied once to the total, not to each die. 4d6+2 has a minimum of 6 and a maximum of 26, not a minimum of 12. A negative modifier works the same way and is entered with a minus sign.

Changing the modifier does not reroll the dice. That is deliberate: a modifier is not part of the roll, so adjusting it recalculates the total while leaving the dice as they fell — the same thing that happens when you notice a bonus after the dice have stopped.

What makes a digital roll fair

Two separate things have to be right, and generators commonly get the second one wrong.

The first is unpredictability. Rolls here come from your browser’s cryptographically secure random number generator, the same facility that backs encryption keys — not the ordinary random function built into JavaScript, whose future output can be predicted from output already seen.

The second is uniformity. The obvious way to turn a random value into a die face is to divide by the number of sides and keep the remainder. That is subtly biased: unless the number of sides divides the generator’s range evenly, the low faces come up slightly more often than the high ones. On a d20 the effect is invisible to a player and completely real in the numbers. This tool discards values that would land in the uneven part of the range and draws again, so every face is genuinely equally likely.

Averages, and why they feel wrong

A single die is flat: every face equally likely, average (sides + 1) ÷ 2. A d20 averages 10.5, a d6 averages 3.5.

Several dice added together are not flat at all. With 2d6 there is one way to make 2 and six ways to make 7, so 7 comes up six times as often as either extreme. This is why 3d6 clusters around 10–11 and why swapping “roll 3d6” for “roll 1d18” changes a game completely, even though both span a similar range.

The arithmetic line makes that visible: across a handful of dice you will usually see a spread rather than a cluster, and across many dice the total will sit close to the middle far more often than not.

Streaks are normal

Rolling the same number several times in a row feels like evidence that something is broken. It usually is not. Three identical results on a d20 has roughly a one in eight thousand chance — unlikely for you on a given evening, and unremarkable across the number of rolls a page like this handles.

A generator that avoided repeats to look more convincing would be the biased one. Real randomness has no memory: the die does not know what it did last time, and the next roll is exactly as likely to be a 20 as it ever was.

Frequently asked questions

Is an online dice roller actually fair?

This one is. Rolls come from your browser's cryptographically secure random number generator, and each die is drawn with a method that keeps every face equally likely. The common shortcut — taking a random value and using the remainder after dividing by the number of sides — quietly favors the low faces, so this tool discards those values and draws again instead.

How do I roll something like 4d6+2?

Set How many to 4, choose d6, and put 2 in Modifier. The big number is the total including the modifier, and the line underneath shows each die and the arithmetic. The modifier can be negative.

Why doesn't changing the modifier reroll the dice?

Because a modifier is not part of the roll. Adjusting it changes the total but leaves the dice as they fell, which is what happens at a table. Use the refresh button to roll again.

How many dice can I roll at once?

Up to 100. Beyond that the individual results stop being readable and the tool becomes a random number generator, which is a better fit for that job.

How is a d100 rolled?

As a single draw between 1 and 100. Rolling two ten-sided dice for tens and units gives exactly the same distribution, so the result is equivalent — this way just skips explaining percentile pairs.

I rolled three 20s in a row. Is it broken?

Almost certainly not. Runs are what real randomness looks like; three identical results on a d20 has about a one in 8,000 chance, which happens routinely across many rolls. A generator that avoided repeats to seem more random would be the biased one.