Which dice do I roll in D&D, and when?

The simplest useful rule

D&D uses several dice, but you do not need to choose one from memory each time you act. When the outcome is uncertain, the table very often starts with a d20. But not every effect begins with a success roll: a healing potion tells you directly to roll its healing dice. Your character sheet, spell, item or feature will name the die.

Your character sheet, a spell description, a class feature, or the Dungeon Master will normally tell you which die to roll. A weapon entry says 1d8, a spell says 2d6, a class feature says roll a d10. Your job is to recognise the instruction and roll what it names, not to recall every possible die combination before play begins.

The d20: checks, attacks and saves

The same physical die is used for the three common beginner-facing rolls. The difference is which modifier applies and why you are rolling:

• Ability checks You try to do something where success is uncertain, such as persuading a guard, spotting a hidden door, or recalling lore. The DM names the relevant ability or skill, you roll a d20, add that modifier, and compare the total with a target number the DM has set. The roll represents your attempt, not the final consequence.
• Attack rolls You try to hit a creature with a weapon or a spell that requires an attack. Roll a d20 and add the listed attack bonus, such as +5. That total normally already includes your ability modifier and any applicable proficiency bonus, so do not add those again. Apply any additional modifier the rule or DM specifies. Usually, a total that meets or beats the target's Armour Class hits; a natural 20 always hits, and a natural 1 always misses. On a hit, roll the listed damage separately. For full details, see the [2024 Basic Rules: Playing the Game](https://www.dndbeyond.com/sources/dnd/br-2024/playing-the-game) or [2014 Basic Rules: Combat](https://www.dndbeyond.com/sources/dnd/basic-rules-2014/combat).
• Saving throws Something happens to you and you try to resist it, such as dodging a fireball, withstanding poison, or holding firm against a spell. The DM tells you which ability is being tested and what number to meet or beat. Roll a d20, add the saving throw modifier for that ability, and compare. The roll does not determine what you do, it determines how you hold up against what is already happening.

The other dice: damage, healing and amounts

A damaging attack that requires an attack roll uses its listed damage dice on a hit. Other effects name their dice directly:

• d4, d6, d8, d10, d12 These are the dice most often linked to an amount. A dagger might deal 1d4 damage, a longsword 1d8, a greataxe 1d12, a fire bolt 1d10, and a common [2024 Potion of Healing](https://www.dndbeyond.com/magic-items/8960641-potion-of-healing) restores 2d4 + 2 hit points. Larger dice are not inherently better or worse, they simply reflect the design of that weapon, spell or feature. Your sheet tells you which one applies.
• d10 as percentile and d100 Two ten-sided dice can be rolled as percentile dice to generate a number from 1 to 100, often written as d100. New players meet this less often, usually on a table that says roll d100 for a random effect. Before rolling, designate one die as tens and the other as ones: 70 and 3 means 73, while 00 and 0 means 100. See the [2024 Basic Rules: Playing the Game](https://www.dndbeyond.com/sources/dnd/br-2024/playing-the-game) or [2014 Basic Rules: Introduction](https://www.dndbeyond.com/sources/dnd/basic-rules-2014/introduction).
• Read the source, not your memory If you cast [2024 Cure Wounds](https://www.dndbeyond.com/spells/2619079-cure-wounds), the spell says how many dice to roll for healing. If you swing a weapon, the weapon entry says which die to use. If a feature grants extra damage, it names the die. When you level up or pick a new spell, check what that new option says to roll and note it where you will see it next session.

How to read dice notation

D&D writes dice as a short code. Once you recognise the pattern, every entry on your sheet makes sense:

• 1d20 Roll one twenty-sided die. This is the form you will see for most checks, attacks and saves. Roll the die, add the modifier the DM or sheet names, and compare with the target number.
• 2d6 Roll two six-sided dice and add them together. You will see this for damage and healing, for example a spell that deals 2d6 fire damage. Roll both dice, add them, then apply any modifier shown.
• 1d8 + 3 Roll one eight-sided die and add 3. The number after the plus sign is a fixed modifier, often from your ability or a feature. Roll the die, add the number, and that total is the result. The same pattern works with other dice, such as 1d10 + 5 or 2d4 + 2.
• Modifiers and target numbers A plus sign after the dice always means add that number after rolling. The d20 rolls also add a modifier before you compare with a target number such as Armour Class or a Difficulty Class (often shortened to AC or DC at the table). Your sheet lists your common modifiers so you can find them quickly when the DM names the roll.

Advantage and disadvantage: rolling two d20s

Advantage and disadvantage are a simple way for the rules to reflect a better or worse chance without changing your modifier. When you have advantage on a d20 roll, roll two d20s and keep the higher result. When you have disadvantage, roll two d20s and keep the lower result. Add your normal modifier afterwards, just as you would for a single d20 roll.

The DM or a rule will tell you when advantage or disadvantage applies, for example when you attack a target you cannot see, or when an ally helps you in a way the rules recognise. You do not need to memorise every interaction. If both advantage and disadvantage apply to the same roll, they normally cancel out and you roll a single d20. For detailed interactions and edge cases, check the official rules or a current System Reference Document rather than trying to learn every exception at the table.

Before you roll, check this

A quick routine that keeps dice handling calm during play:

• Know where your common d20 modifiers are written: ability checks, attack bonuses, and saving throws.
• For your usual weapon, spell, or feature, note the exact dice code (such as 1d8 + 3 or 2d6) where you will see it when the DM calls for damage or healing.
• When the DM asks for a roll, confirm which ability or skill to add rather than assuming.
• On advantage or disadvantage, roll two d20s and keep the higher or lower result, then add your normal modifier.
• If you are unsure which die to use, ask the DM or check the spell or weapon entry instead of guessing.
• After the session, update your notes with any new dice a new spell or feature introduced so it is ready next time.