OneTaskBy Tim King · Updated
3D Dice Roller
Roll Real Physics Dice (D4, D6, D8, D10, D12, D20) in Your Browser
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How the 3D Dice Roller works
This 3D dice roller rolls real physics dice from standard notation. Type the dice you want in the usual shorthand (2d6, 1d20, 3d8 + 1d12, up to twenty dice at a time), press Roll or click the tray, and the dice drop in, bounce off the rim and skid to a stop on the felt. Once every die has settled the tool reads the face that ended up on top and shows each result, the total, the highest and the lowest. Drag to orbit the tray, scroll to zoom, and Save PNG to keep a picture of the throw.
3D dice roller: getting a good result
Most online dice rollers pick a number with a random number generator and draw a picture of it. This one throws actual dice. Each die is a real polyhedron, a tetrahedron for the d4, a cube for the d6, an octahedron for the d8, a pentagonal trapezohedron for the d10, a dodecahedron for the d12 and an icosahedron for the d20, and it is dropped into a 3D physics engine that runs in your browser. The dice collide with the tray, the rim and each other, tumble with friction and bounce with a little restitution, exactly as a handful of real dice would.
How the result is read. When the dice have all come to rest the tool finds, for each one, the face whose outward direction points most nearly straight up, and reports the number printed there. The d4 is the exception: a tetrahedron rests on a face with a point at the top, so its result is read from the face on the table, the same convention many physical d4s use. If a die is still creeping or wobbling after ten seconds the tool reads it as it stands rather than waiting forever.
Is it fair? The starting position, orientation and spin of every die are randomised for each throw, and after several bounces the outcome is as unpredictable as a real roll. It is not a substitute for a cryptographic random number generator, but neither is a real die, and for board games and tabletop RPGs it is a great deal more satisfying to watch.
Shorthand. Write the count, the letter d and the number of faces: 2d6 means two six-sided dice, d20 on its own means one twenty-sided die, and you can chain sets with spaces or plus signs, such as 1d20 + 2d6 + 1d4. Only the six standard polyhedral sizes are available, and the tray holds up to twenty dice per throw. Everything runs locally in the page; nothing is sent anywhere, and Pause, Fullscreen and Save PNG work as usual.
FAQ
Why is the d4 read from the bottom?
A tetrahedron rests on a face with a point uppermost, so there is no top face to read. Reading the face on the table matches the convention on most physical d4s, where the number at the base of each side is the result.
Can I roll a d100 or a d3?
No, only the six standard polyhedral dice. For a d100 roll 2d10 and read one as tens; for a d3 roll a d6 and halve it, rounding up.
Why is the result sometimes read before the dice stop?
A die that keeps creeping or rocking after ten seconds is read as it stands so the roll can finish. It is rare and usually happens when a die is wedged against the rim.
Can I add a modifier like 1d20+5?
Not in the box; only dice terms are parsed. Roll the dice and add the modifier to the total
yourself. A roll like 2d6+1d4 works because every term is dice.
See also: all Simulations & Screensavers tools, Images, Audio, Video & Screen, PDF, SVG, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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