Roll d20

About d20

Faces

20

Chance of any face

5%

Average roll

10.5

To see every face

~72 rolls

A 20-sided die has 20 faces, so every number comes up 5% of the time and the average roll is 10.5. Rolling until all 20 faces have shown their turn takes about 72 rolls.

Other dice

Each one on its own page

• Coin flip

  Heads or tails, with a running tally of the flips so far.

• Random number

  A number out of any range, with no repeats if you want.

• Random letter

  A letter of the alphabet — all of them, or only vowels.

The rest of the kit

• Name wheel

  Spin to pick a pupil. Nobody is picked twice until everyone has had a turn.

• Random groups

  Split the class into even groups in one click, by number of groups or by size.

• Classroom timer

  A countdown the back row can read, with a bar that turns amber, then red.

• Stopwatch

  Start, lap, stop. Laps with splits, fastest and slowest marked.

• Focus timer

  Work and break rounds that run by themselves, 25 and 5 or your own.