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Regular Dodecahedron • 12 Faces

D12 Roller

A D12 is a 12-sided die shaped like a regular dodecahedron with outcomes from 1 to 12. Each face has an 8.33% chance of occurring.

Dice Tray
1d12
Click button or press Space to roll
Total Result
-- Ready
Roll Breakdown
Roll the dice to see outcome
Select Die Type Standard Polyhedral Set
Roll Configuration Quantity & Modifiers
1 – 100
2 – 1000
± bonus
âš™ Advanced Expression (NdM±K) â–¼
Shortcuts:
âš¡ Quick Dice Rolls 1-Click instant roll

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Exact Mathematical Probability

Combinatorial Engine

Calculates discrete binomial distributions, probability density, and cumulative odds for the active dice expression.

Range (Min - Max) --
Theoretical Average --
Most Likely (Mode) --
Total Permutations --
Query Target Probability
Exactly ( = X ) --%
At Least ( ≥ X ) --%
At Most ( ≤ X ) --%
Probability Density Distribution Hover / tap bar to view odds
View Full Probability Table & Combinations â–¼
Total Ways Exact % ≥ At Least ≤ At Most

Roll N Times (Multi-Trial Simulation)

Execute up to 10,000 repeated trials to calculate empirical distributions and statistics.

Trials --
Mean (Avg) --
Median --
Mode --
Min --
Max --
Sum --

Empirical Frequency Table

Roll Total Hits (Count) Frequency Bar Percentage
Click "Run Trials" to simulate rolls and generate frequency data.

About the D12 (Regular Dodecahedron)

The D12 is mathematically one of the most balanced Platonic solids. In tabletop gaming, it is beloved as the signature die of Barbarians (their hit die and greataxe damage) and for determining hours of the day, months of the year, or astrological constellations.

Geometric Properties

Regular dodecahedron featuring 12 congruent regular pentagonal faces, 20 vertices, and 30 edges. Its smooth rolling dynamics make it one of the most satisfying physical dice.

Common Tabletop & Gaming Uses

  • • Greataxe damage (1d12 slashing damage)
  • • Barbarian class hit die
  • • Spells like Witch Bolt and Poison Spray at higher tiers
  • • Randomizing clock hours (1–12) or zodiac/calendar charts

D12 Probability Basics

Each face from 1 to 12 has an equal 8.333% probability.

Minimum Roll 1
Maximum Roll 12
Theoretical Average 6.5
Odds Per Face 1 in 12 (8.33%)
Face Value Theoretical Odds Exact Percentage
1 1/12 8.33%
2 1/12 8.33%
3 1/12 8.33%
4 1/12 8.33%
5 1/12 8.33%
6 1/12 8.33%
7 1/12 8.33%
8 1/12 8.33%
9 1/12 8.33%
10 1/12 8.33%
11 1/12 8.33%
12 1/12 8.33%

Frequently Asked Questions About D12

Which is better: 1D12 or 2D6?
1D12 has an average of 6.5 with a flat 8.33% chance for every number (including 12). 2D6 has a higher average of 7.0 and a bell curve peaking at 7 (16.67%), but only a 2.78% chance of rolling a 12. Greatswords (2d6) are more consistent, while Greataxes (1d12) produce more extreme maximum rolls.
What is the average roll of a D12?
The mathematical expected average of a 12-sided die is (1 + 12) / 2 = 6.5.