What dice notation is supported?

Standard NdS notation — for example 3d8 or 1d20 — plus an optional +/- modifier and an optional keep-highest or keep-lowest clause written as khN or klN, such as 4d6kh3.

What does 4d6kh3 mean?

It means roll four six-sided dice and keep the highest three, dropping the lowest. This is the classic Dungeons & Dragons method for rolling an ability score — for example rolling 5, 4, 3, 1 keeps 5+4+3 = 12.

How do I roll with advantage or disadvantage?

Advantage is rolling two d20 and keeping the higher: 2d20kh1. Disadvantage keeps the lower: 2d20kl1. Add your modifier as usual, for example 2d20kh1+5.

Are the rolls genuinely random?

Yes. Every die uses the browser's Web Crypto API with modulo bias removed, so each face is equally likely on every roll — no predictable pseudo-random sequence.

What dice can I roll and how many?

Any number of sides from 2 up to 1000 and from 1 up to 100 dice per roll, so d4, d6, d8, d10, d12, d20 and d100 are all supported, along with unusual dice. The keep clause must keep at least one die and no more than the number rolled.

Does it keep a history of my rolls?

Yes. The tool shows a short list of your recent rolls with their notation and totals, so you can refer back to the last few without re-rolling.

Is my roll data sent anywhere?

No. All parsing and rolling happens locally in your browser. Nothing is uploaded, logged or recorded.

D&D Dice Roller — Gera Tools

D&D dice roller with notation

Roll using the dice notation you already know — NdS with an optional +/- modifier and keep-highest / keep-lowest clauses. It is made for tabletop role-playing games like Dungeons & Dragons, where ability scores, attacks and saving throws are all expressed in dice notation.

How it works

You type notation such as 2d6+3 or 4d6kh3, and the parser reads four parts: the count (how many dice), the sides per die, an optional keep clause (khN keep highest N, klN keep lowest N), and an optional +/- modifier. Each die is rolled with the browser’s Web Crypto API using rejection sampling to remove modulo bias, so every face is equally likely. If a keep clause is present, the dice are sorted and only the best (or worst) N are summed; the modifier is then added to give the total.

Example

Roll 4d6kh3 (the classic ability-score roll):

rolls [5, 4, 3, 1] → keep highest 3 → [5, 4, 3] = 12

Notation	Meaning	Total range
1d20+5	d20 plus 5 (attack)	6–25
4d6kh3	4d6 keep highest 3	3–18
2d20kh1	advantage (keep higher d20)	1–20
2d20kl1	disadvantage (keep lower d20)	1–20
8d6	fireball damage	8–48

You see the individual dice, which were kept, the modifier and the total, plus a short history of recent rolls. Everything runs in your browser — nothing is uploaded.