Dice Roller

About this tool

Rolling physical dice is satisfying until the D4 slides under the couch or you are playing remotely and the game master needs to roll fifteen dice at once. Dice Roller accepts standard NdM±K notation — type 4d6, 2d20+5, or 8d6, click Apply, then Roll Dice to get every individual die value plus the final total. You can also set Dice count (1–100), Sides per die (2–1000) and Modifier directly, and the notation updates to match. A Rolls readout shows each face separately so the whole table can verify the math, and a session history keeps your last 25 rolls visible for the inevitable 'wait, what was that number?' moment. Powered by the Web Crypto API, every roll is as fair as a freshly opened set of polyhedral dice. Whether you are a tabletop RPG player generating ability scores, a board-game designer testing probability, or a math teacher demonstrating distributions, this tool handles the roll and gets out of the way.

Why use it

• Full NdM Notation: Type 2d20+5 or 4d6-1 directly into the input without touching a dropdown — the parser handles any standard dice expression including modifiers in both positive and negative form.

• Per-Die Breakdown: Every individual die face is shown separately alongside the total, so the whole table can verify that a fireball's 8d6 added up correctly and nobody is hiding a low roll.

• Session Roll History: Recent rolls persist in a log below the input throughout your session so you can audit a critical hit, compare ability score sets, or settle a table dispute about what was rolled three turns ago.

• Modifier Math Built-In: Add or subtract flat modifiers directly in the notation and the tool computes the adjusted total automatically — no mental arithmetic required while tracking initiative in a fast-paced combat round.

• Manual Controls Available: Step through count, sides, and modifier with increment controls if you prefer clicking over typing, making it friendlier for new players who haven't memorized NdM shorthand yet.

• Cryptographic Fairness: Each die face is sampled from the Web Crypto API, giving you genuine uniform randomness across the full face range — no Math.random clustering that could skew low rolls on large dice.

How to use

1. Type a dice expression in the Dice notation field using NdM±K format — for example 2d6, 1d20+5, or 4d6-1 — and click Apply to load it into the controls.
2. Or skip the notation and set Dice count, Sides per die and Modifier directly; the notation field updates as you type.
3. Click Roll Dice. Note that Roll uses the current control values, so click Apply first if you typed a new expression.
4. Read each individual die result in the Rolls box and the final total, including your modifier, in the Total box.
5. Review the History list to compare this roll against your previous ones; click Clear History to start fresh.

When it helps

• When playing a tabletop RPG remotely and you need a shared, trusted dice source for the whole table
• When a physical die is lost, missing, or you need a polyhedral type you don't own
• When a board-game designer needs to rapidly sample a probability distribution for balance testing
• When a math or statistics teacher needs live dice data for a chi-square or probability lesson
• When generating D&D ability scores using the 4d6 drop-lowest method
• When a game master needs to roll large dice pools quickly without hunting under the table for a wayward D4

Examples

Tips

• For D&D ability score generation, roll 4d6 six times and manually drop the lowest die from each set for the standard method.
• Use the Modifier field for proficiency or attribute bonuses and keep your character sheet open beside the tool so you do not forget which modifier applies.
• Screenshot the session history after combat encounters to settle any post-game disputes about whether that critical hit was real.
• Switch to the manual count-and-sides controls when explaining NdM notation to a new player — the notation field updates live so they can see how the shorthand is built.
• For statistical analysis, roll dozens of times, then copy the History text into a spreadsheet and split out the totals to visualize the distribution curve.

Frequently Asked Questions

Glossary

NdM Notation

Standard tabletop dice notation where N is the number of dice and M is the number of sides on each die. For example, 3d8 means roll three eight-sided dice and sum the results.

Modifier

A flat number added to or subtracted from a dice total after rolling. In tabletop RPGs, modifiers commonly represent ability bonuses, proficiency, or magical effects applied on top of the raw roll.

Critical Hit

In many tabletop RPGs, a natural maximum roll on an attack die that triggers additional effects or damage. Seeing every individual die helps players confirm a critical hit was legitimate.

Polyhedral Die

Any die with more or fewer than six sides. Tabletop RPGs commonly use d4, d6, d8, d10, d12, d20, and d100 shapes, each producing uniform random results across their face count.

Drop Lowest

A dice pool method where you roll more dice than you need and discard the lowest value before summing. The D&D 5e 4d6 ability score method uses drop-lowest to skew results slightly higher.

Advantage / Disadvantage

A D&D 5e mechanic where you roll the attack or check die twice and take the higher result (advantage) or lower result (disadvantage), shifting the probability distribution significantly without changing the die.