How is each die result generated?

Each die uses JavaScript's Math.random() to produce a pseudo-random integer between 1 and the number of sides, inclusive. No results are pre-computed; use physical dice or a cryptographic random source when verifiable randomness is required.

What does the modifier do?

The modifier is an integer added to (or subtracted from) the sum of all individual die results. Enter a positive number like 3 to add +3, or a negative number like -2 to subtract 2.

How many dice can I roll at once?

You can roll 1 to 20 dice simultaneously. All individual results are shown side by side along with the combined total.

How many rolls does the history keep?

The history panel stores your last 20 rolls for the current session. It is cleared when you refresh the page or click Clear History.

What does a critical hit or fumble look like?

When you roll the maximum value on a die it is highlighted in green (critical hit). A roll of 1 is highlighted in red (critical fumble / natural 1).

Is this tool free and private?

Yes. The roller runs entirely in your browser. No data is sent to any server, and there are no accounts or tracking.

What does 1d20+5 mean?

Roll one twenty-sided die and add 5. Set Quantity to 1, pick d20 and enter 5 as the modifier. The result ranges from 6 to 25.

How do I roll with advantage or disadvantage?

Pick d20, enter your modifier and click Advantage or Disadvantage under Roll mode, then press Roll. The tool rolls two d20s, keeps the higher (advantage) or lower (disadvantage) die, adds the modifier and shows the dropped die greyed out.

D20 Roller

Roll any RPG die (d4 through d100) with a custom quantity and modifier — see each result and the running history log.

A d20 roller picks a whole number from 1 to 20, each with a 5% chance.

Choose Your Die

Quantity

Modifier

Roll mode

Quick answer

A d20 roller picks a whole number from 1 to 20, each with a 5% chance. Pick d20, add your modifier and press Roll. For advantage or disadvantage, click that button: the roller throws two d20s, keeps the higher or lower one and adds your modifier.

Examples

Roll	Chance
Natural 20 on one d20	5% (1 in 20)
10 or higher on one d20	55%
15 or higher on one d20	30%
Natural 20 with advantage (2d20, keep higher)	9.75%
Natural 20 with disadvantage (2d20, keep lower)	0.25%

Roll the d20.

Summary

Roll any RPG die (d4 through d100) with a custom quantity and modifier — see each result and the running history log.

How it works

Select a die type by clicking one of the die buttons (d4, d6, d8, d10, d12, d20, or d100).
Enter the number of dice to roll in the Quantity field (1 to 20).
Optionally enter a modifier — a positive or negative integer added to the total.
For advantage or disadvantage, click that Roll mode button: two dice are rolled and the higher or lower one is kept.
Click Roll or press Enter to roll and see individual die results and the grand total.
Consecutive rolls are logged in the History panel at the bottom for easy reference.
Click Clear History to wipe the log and start fresh.

Use cases

Roll attack rolls, damage dice, and saving throws in D&D 5e or Pathfinder.
Quickly generate a d100 percentile roll for random-event tables.
Roll 4d6 and drop the lowest for character stat generation.
Test homebrew game mechanics without hunting for physical dice.
Run a remote tabletop session and share results with the group.
Roll initiative for an entire party in seconds.

Frequently Asked Questions

Last updated: 2026-05-29 · Reviewed by Nham Vu