Tabletop guide / Published September 16, 2026

How Dice Rolling Works in Tabletop Games

Dice notation: reading "2d6+3"

Tabletop rules use a shorthand for dice: [number]d[sides]+[modifier].

• 1d20 = roll one twenty-sided die.
• 2d6 = roll two six-sided dice and add them (result 2–12).
• 2d6+3 = roll two d6, add them, then add 3.
• 1d8+4 = roll one d8 and add 4 — a typical weapon-damage roll.

Once you can read this, you can read almost any rulebook. Which die is which is covered in the 7-piece polyhedral set explained.

Target numbers (the DC)

Most rolls are a check against a target number — in D&D it's the Difficulty Class (DC). You roll a d20, add the relevant modifier, and if the total meets or beats the DC, you succeed. Easy tasks have a low DC (10), hard ones a high DC (20+). Combat works the same way: your attack roll tries to beat the target's Armor Class.

Modifiers

A modifier is a bonus or penalty added to the die from your character's skills, ability scores, or situation. A +5 modifier turns a d20 roll of 12 into a 17. Modifiers are how a character's training tilts the odds without removing the dice's uncertainty.

Advantage and disadvantage

A popular modern mechanic: when you have advantage, roll two d20 and keep the higher; with disadvantage, roll two and keep the lower. It's a fast, intuitive way to represent favorable or unfavorable circumstances — and a big reason players like having spare d20s on hand.

Why fair, balanced dice matter

If dice decide success and failure, a biased die quietly warps the game. Quality manufacturing — consistent density, true edges, clean numbering — is what keeps rolls fair for tabletop play. You can check a die yourself with the salt-water float test, explained in the dice balance guide. (Artistic sets like liquid-core resin have more internal variation and are best treated as collector dice — see the resin dice guide.)

Putting it together

1. The DM sets a DC for an uncertain action.
2. You roll 1d20 (twice if you have advantage) and add your modifier.
3. Meet or beat the DC and you succeed; damage or effects then use notation like 2d6+3.

Want dice that roll true and read clearly? See the best dice for D&D or browse in-stock dice.

Frequently asked questions

What does 2d6 mean?

It is dice notation meaning "roll two six-sided dice and add the results," giving a total from 2 to 12. The format is [number]d[sides], so 1d20 is one twenty-sided die and 3d8 is three eight-sided dice. A trailing number like 2d6+3 means add that modifier to the total.

What is a DC in D&D?

DC stands for Difficulty Class — the target number for a check. You roll a d20, add the relevant modifier, and if the total meets or beats the DC, you succeed. Easy tasks use a low DC around 10 and hard tasks 20 or higher. Combat uses the same idea against a target's Armor Class.

How do advantage and disadvantage work?

With advantage you roll two d20 and keep the higher result; with disadvantage you roll two d20 and keep the lower. It is a quick way to represent favorable or unfavorable circumstances without adding fiddly bonuses, and it is why many players like keeping spare d20s handy.

What is a modifier in a dice roll?

A modifier is a bonus or penalty added to your die roll based on your character's ability scores, skills, or the situation. For example, a +5 modifier turns a d20 roll of 12 into 17. Modifiers tilt the odds toward a trained character while keeping the dice's uncertainty.

Do unbalanced dice really affect the game?

Yes. Because dice decide success and failure, a biased die skews outcomes over many rolls. Consistent density, true edges, and clean numbering keep rolls fair for tabletop play. You can test a die with the salt-water float method; note that artistic sets like liquid-core resin have more internal variation and are best used as collector dice.