D12 dice roller

Roll a 12-sided die online

Here the dice roller opens on a 12-sided die, the d12. Click "Roll the dice" or the die itself, or press the space bar: the die wobbles for half a second, then shows a number from 1 to 12. Your browser's cryptographic random number generator does the drawing, every side has the same chance, and no data is sent.

You can roll up to 20 dice at once and get the total, change the "Number of sides" or use the "Quick picks". "Latest rolls" shows your last 12 rolls.

What is a d12 used for?

The d12 is a dodecahedron, one of the five Platonic solids: twelve identical pentagonal faces. It often stays at the bottom of the bag, yet it has uses of its own.

• Picking a month: 1 = January, 12 = December. To set the date of a party, a challenge or a scene in a story.
• Picking an hour on the clock: the twelve hours of a clock face, for a meeting time in a mystery game or a treasure hunt.
• Tabletop role-playing games: damage for heavy two-handed weapons such as a great axe, and hit points for the toughest characters.
• Handing out 12 tasks or picking one player in a group of 12.

The odds with a d12

Each side has a 1 in 12 chance, about 8.33%. The average is (1 + 2 + … + 12) ÷ 12 = 78 ÷ 12 = 6.5. Over two rolls, the chance of seeing at least one 12 is 1 − (11/12)² = 23/144 ≈ 15.97%.

A d12 is not a substitute for 2d6. Both top out at 12, but 2d6 can never give 1 and lands on 7 in 16.67% of rolls, while a d12 gives every value from 1 to 12 with 8.33%.

Frequently asked questions

How do I pick a month without favoring any?

Roll a single 12-sided die: every month has exactly the same chance. With 2d6, mid-year months would come up far more often and January never.

Can I roll several d12?

Yes, up to 20. Enter the number in "Number of dice": each die and the sum are shown.