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It's sometimes handy to know the probabilities of an action succeeding in TFT. Since TFT uses 6-sided dice exclusively (as does GURPS), these tables do not include any other possibilities. The first table gives the probability of rolling a specific number; the second table gives the probability of rolling less than or equal to a specific number.

This table gives the probability of rolling a particular number on a set of so many 6-sided dice.

Roll | 1 die | 2 dice | 3 dice | 4 dice | 5 dice |
---|---|---|---|---|---|

1 | 1/6 (16.667%) | 0 | 0 | 0 | 0 |

2 | 1/6 (16.667%) | 1/36 (2.778%) | 0 | 0 | 0 |

3 | 1/6 (16.667%) | 2/36 (5.556%) | 1/216 (0.463%) | 0 | 0 |

4 | 1/6 (16.667%) | 3/36 (8.333%) | 3/216 (1.389%) | 1/1296 (0.077%) | 0 |

5 | 1/6 (16.667%) | 4/36 (11.111%) | 6/216 (2.778%) | 4/1296 (0.309%) | 1/7776 (0.013%) |

6 | 1/6 (16.667%) | 5/36 (13.889%) | 10/216 (4.630%) | 10/1296 (0.772%) | 5/7776 (0.064%) |

7 | 0 | 6/36 (16.667%) | 15/216 (6.944%) | 20/1296 (1.543%) | 15/7776 (0.193%) |

8 | 0 | 5/36 (13.889%) | 21/216 (9.722%) | 35/1296 (2.701%) | 35/7776 (0.450%) |

9 | 0 | 4/36 (11.111%) | 25/216 (11.574%) | 56/1296 (4.321%) | 70/7776 (0.900%) |

10 | 0 | 3/36 (8.333%) | 27/216 (12.500%) | 80/1296 (6.173%) | 126/7776 (1.620%) |

11 | 0 | 2/36 (5.556%) | 27/216 (12.500%) | 104/1296 (8.025%) | 205/7776 (2.636%) |

12 | 0 | 1/36 (2.778%) | 25/216 (11.574%) | 125/1296 (9.645%) | 305/7776 (3.922%) |

13 | 0 | 0 | 21/216 (9.722%) | 140/1296 (10.802%) | 420/7776 (5.401%) |

14 | 0 | 0 | 15/216 (6.944%) | 146/1296 (11.265%) | 540/7776 (6.944%) |

15 | 0 | 0 | 10/216 (4.630%) | 140/1296 (10.802%) | 651/7776 (8.372%) |

16 | 0 | 0 | 6/216 (2.778%) | 125/1296 (9.645%) | 735/7776 (9.452%) |

17 | 0 | 0 | 3/216 (1.389%) | 104/1296 (8.025%) | 780/7776 (10.031%) |

18 | 0 | 0 | 1/216 (0.463%) | 80/1296 (6.173%) | 780/7776 (10.031%) |

19 | 0 | 0 | 0 | 56/1296 (4.321%) | 735/7776 (9.452%) |

20 | 0 | 0 | 0 | 35/1296 (2.701%) | 651/7776 (8.372%) |

21 | 0 | 0 | 0 | 20/1296 (1.543%) | 540/7776 (6.944%) |

22 | 0 | 0 | 0 | 10/1296 (0.772%) | 420/7776 (5.401%) |

23 | 0 | 0 | 0 | 4/1296 (0.309%) | 305/7776 (3.922%) |

24 | 0 | 0 | 0 | 1/1296 (0.077%) | 205/7776 (2.636%) |

25 | 0 | 0 | 0 | 0 | 126/7776 (1.620%) |

26 | 0 | 0 | 0 | 0 | 70/7776 (0.900%) |

27 | 0 | 0 | 0 | 0 | 35/7776 (0.450%) |

28 | 0 | 0 | 0 | 0 | 15/7776 (0.193%) |

29 | 0 | 0 | 0 | 0 | 5/7776 (0.064%) |

30 | 0 | 0 | 0 | 0 | 1/7776 (0.013%) |

This table gives the probability of rolling a particular number
*or less* on a set of so many 6-sided dice. It can also be used
to find the probability of rolling a particular number *or more*.
Since the probability of rolling N or more is the same as the
probability of *not* rolling N-1 or less, simply look up the
N-1 value on this table, and subtract it from 1 or 100%. For example,
to find the probability of rolling 8 or more on 3 dice, look up
the probability of rolling 7 or less, which is 35/216 or 16.204%.
Subtract that from 1, giving 181/216 (216 - 35 = 181) or 83.796%.

Roll | 1 die | 2 dice | 3 dice | 4 dice | 5 dice |
---|---|---|---|---|---|

1 | 1/6 (16.667%) | 0 | 0 | 0 | 0 |

2 | 2/6 (33.333%) | 1/36 (2.778%) | 0 | 0 | 0 |

3 | 3/6 (50.000%) | 3/36 (8.333%) | 1/216 (0.463%) | 0 | 0 |

4 | 4/6 (66.667%) | 6/36 (16.667%) | 4/216 (1.852%) | 1/1296 (0.077%) | 0 |

5 | 5/6 (83.333%) | 10/36 (27.778%) | 10/216 (4.630%) | 5/1296 (0.386%) | 1/7776 (0.013%) |

6 | 6/6 (100%) | 15/36 (41.667%) | 20/216 (9.259%) | 15/1296 (1.157%) | 6/7776 (0.077%) |

7 | 100% | 21/36 (58.333%) | 35/216 (16.204%) | 35/1296 (2.701%) | 21/7776 (0.270%) |

8 | 100% | 26/36 (72.222%) | 56/216 (25.926%) | 70/1296 (5.401%) | 56/7776 (0.720%) |

9 | 100% | 30/36 (83.333%) | 81/216 (37.500%) | 126/1296 (9.722%) | 126/7776 (1.620%) |

10 | 100% | 33/36 (91.667%) | 108/216 (50.000%) | 206/1296 (15.895%) | 252/7776 (3.241%) |

11 | 100% | 35/36 (97.222%) | 135/216 (62.500%) | 310/1296 (23.920%) | 457/7776 (5.877%) |

12 | 100% | 36/36 (100%) | 160/216 (74.074%) | 435/1296 (33.565%) | 762/7776 (9.799%) |

13 | 100% | 100% | 181/216 (83.796%) | 575/1296 (44.367%) | 1182/7776 (15.201%) |

14 | 100% | 100% | 196/216 (90.741%) | 721/1296 (55.633%) | 1722/7776 (22.145%) |

15 | 100% | 100% | 206/216 (95.370%) | 861/1296 (66.435%) | 2373/7776 (30.517%) |

16 | 100% | 100% | 212/216 (98.148%) | 986/1296 (76.080%) | 3108/7776 (39.969%) |

17 | 100% | 100% | 215/216 (99.537%) | 1090/1296 (84.105%) | 3888/7776 (50.000%) |

18 | 100% | 100% | 216/216 (100%) | 1170/1296 (90.278%) | 4668/7776 (60.031%) |

19 | 100% | 100% | 100% | 1226/1296 (94.599%) | 5403/7776 (69.483%) |

20 | 100% | 100% | 100% | 1261/1296 (97.299%) | 6054/7776 (77.855%) |

21 | 100% | 100% | 100% | 1281/1296 (98.843%) | 6594/7776 (84.799%) |

22 | 100% | 100% | 100% | 1291/1296 (99.614%) | 7014/7776 (90.201%) |

23 | 100% | 100% | 100% | 1295/1296 (99.923%) | 7319/7776 (94.123%) |

24 | 100% | 100% | 100% | 1296/1296 (100%) | 7524/7776 (96.759%) |

25 | 100% | 100% | 100% | 100% | 7650/7776 (98.380%) |

26 | 100% | 100% | 100% | 100% | 7720/7776 (99.280%) |

27 | 100% | 100% | 100% | 100% | 7755/7776 (99.730%) |

28 | 100% | 100% | 100% | 100% | 7770/7776 (99.923%) |

29 | 100% | 100% | 100% | 100% | 7775/7776 (99.987%) |

30 | 100% | 100% | 100% | 100% | 7776/7776 (100%) |

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