Dice Roller

Pick a die, set how many and any modifier, and roll. Advantage and disadvantage are built in for the d20, because that's the roll you'll actually make most. Nothing to install, no sign-up, and it keeps working with no signal.

How to read dice notation

Every roll you'll be asked for at the table is written the same way, and once you can read it you never have to ask again. Take 2d6+3:

• 2 — how many dice to roll
• d6 — how many sides each one has
• +3 — a flat modifier added once to the total

That last point is the one people get wrong. The modifier applies to the whole total, not to each die. 2d6+3 gives you between 5 and 15, not between 8 and 18. If a spell or feature genuinely wants a bonus on every die it will say so explicitly, and that's rare.

Advantage and disadvantage

These are the two most common modifiers to a d20 roll in fifth edition, and both work the same simple way: roll two d20 instead of one, then keep whichever suits.

• Advantage — keep the higher of the two.
• Disadvantage — keep the lower of the two.

Worth knowing what this actually does to your odds: advantage on a d20 is worth roughly a +5 bonus in the middle of the range, where most rolls are decided — considerably more than almost any bonus you can otherwise get. It's usually worth spending a turn to set up.

Critical hits and natural ones

Roll a natural 20 on an attack roll and it's a critical hit: you roll that attack's damage dice twice and then add your modifiers once. Roll a natural 1 on an attack roll and it misses, whatever your bonuses would have made the total.

Both of those apply to attack rolls only. A natural 20 on a saving throw or an ability check is just a 20 — a very good result, but the automatic success and automatic failure rules don't extend to it in the core rules. Plenty of tables house-rule that, and the sheet in our app will happily let you overrule anything, because your DM's word beats ours.

Which die does what

• d20 — attack rolls, ability checks, saving throws. Almost every decision at the table.
• d4, d6, d8, d10, d12 — damage and healing, plus hit dice. Which one depends on the weapon or spell.
• d100 — percentile rolls, usually for random tables and wild magic.

The rolls here use your browser's cryptographic random number generator rather than a basic one, so the distribution is genuinely flat. No dice are cursed. Yours included.