Where the d3 shows up
- Small damage. Older editions and Pathfinder use 1d3 for the smallest hits, such as a Medium character's unarmed strike or a Tiny creature's bite.
- How many? How many goblins come round the corner, how many rounds a spell lingers, how many coins are left in the purse.
- One of three. Three doors, three suspects, three rumors in the tavern. Number them and roll.
Reading a d3
A real d3 is a long triangular die. It cannot stand on its pointed ends, so it always tips onto one of its three long sides, and what points up is a ridge, not a face. Each ridge has its number printed on the two faces beside it, and the number on the top ridge is the roll. The roller above draws it the same way.
Rolling a d3 with a d6
If you have no d3, roll a d6 and halve it, rounding up: 1-2 is a 1, 3-4 is a 2, 5-6 is a 3. It is exactly as fair as a d3. This page just saves you the sum.
Is it fair?
Each number comes up one time in three. The number comes from your browser's cryptographic random generator, and the roller throws away the few values that would tilt the result, so 1, 2 and 3 are dead even.