Wondering what the chance of a given result is in Alternity? Or what change a shift in the bonus or penalty die can have on the probable outcome of a feat check? Check the following tables and find out...
To find out the chance that a character will succeed at an action, find his action/skill/feat total in the relevant column below, then add up all of the percentages from that number to the top of the column. For example, if the character has a skill total of 10, and with all bonuses and penalties he ends up with a +d0 situation die, then the chance that he'll succeed is 5%+5%+5%+5%+5%+5%+5%+5%+5%+5%+0%, or 50%.
The "0:" line in the bonus columns indicates a result where the situation die is greater than the control die (that is, the result is 0 or a negative number, and thus an automatic success).
Bonus dice:
|
d20+d0 0: 0 0% 1: 1 5% 2: 1 5% 3: 1 5% 4: 1 5% 5: 1 5% 6: 1 5% 7: 1 5% 8: 1 5% 9: 1 5% 10: 1 5% 11: 1 5% 12: 1 5% 13: 1 5% 14: 1 5% 15: 1 5% 16: 1 5% 17: 1 5% 18: 1 5% 19: 1 5% 20: 1 5%
Tot: 20 |
d20-d4 0: 10 12.5% 1: 4 5% 2: 4 5% 3: 4 5% 4: 4 5% 5: 4 5% 6: 4 5% 7: 4 5% 8: 4 5% 9: 4 5% 10: 4 5% 11: 4 5% 12: 4 5% 13: 4 5% 14: 4 5% 15: 4 5% 16: 4 5% 17: 3 3.75% 18: 2 2.5% 19: 1 1.25% 20: 0%
Tot: 80 |
d20-d6 0: 21 17.5% 1: 6 5% 2: 6 5% 3: 6 5% 4: 6 5% 5: 6 5% 6: 6 5% 7: 6 5% 8: 6 5% 9: 6 5% 10: 6 5% 11: 6 5% 12: 6 5% 13: 6 5% 14: 6 5% 15: 5 4.166667% 16: 4 3.333333% 17: 3 2.5% 18: 2 1.666667% 19: 1 .8333334% 20: 0%
Tot: 120 |
d20-d8 0: 36 22.5% 1: 8 5% 2: 8 5% 3: 8 5% 4: 8 5% 5: 8 5% 6: 8 5% 7: 8 5% 8: 8 5% 9: 8 5% 10: 8 5% 11: 8 5% 12: 8 5% 13: 7 4.375% 14: 6 3.75% 15: 5 3.125% 16: 4 2.5% 17: 3 1.875% 18: 2 1.25% 19: 1 .625% 20: 0 0%
Tot: 160 |
d20-d12 0: 78 32.5% 1: 12 5% 2: 12 5% 3: 12 5% 4: 12 5% 5: 12 5% 6: 12 5% 7: 12 5% 8: 12 5% 9: 11 4.583333% 10: 10 4.166667% 11: 9 3.75% 12: 8 3.333333% 13: 7 2.916667% 14: 6 2.5% 15: 5 2.083333% 16: 4 1.666667% 17: 3 1.25% 18: 2 .8333334% 19: 1 .4166667% 20: 0 0%
Tot: 240 |
d20-d20 0: 210 52.5% 1: 19 4.75% 2: 18 4.5% 3: 17 4.25% 4: 16 4% 5: 15 3.75% 6: 14 3.5% 7: 13 3.25% 8: 12 3% 9: 11 2.75% 10: 10 2.5% 11: 9 2.25% 12: 8 2% 13: 7 1.75% 14: 6 1.5% 15: 5 1.25% 16: 4 1% 17: 3 .75% 18: 2 .5% 19: 1 .25% 20: 0 0%
Tot: 400 |
|
d20+d4 1: 0 0% 2: 1 1.25% 3: 2 2.5% 4: 3 3.75% 5: 4 5% 6: 4 5% 7: 4 5% 8: 4 5% 9: 4 5% 10: 4 5% 11: 4 5% 12: 4 5% 13: 4 5% 14: 4 5% 15: 4 5% 16: 4 5% 17: 4 5% 18: 4 5% 19: 4 5% 20: 4 5% 21: 4 5% 22: 3 3.75% 23: 2 2.5% 24: 1 1.25%
Tot: 80 |
d20+d6 1: 0 0% 2: 1 .8333334% 3: 2 1.666667% 4: 3 2.5% 5: 4 3.333333% 6: 5 4.166667% 7: 6 5% 8: 6 5% 9: 6 5% 10: 6 5% 11: 6 5% 12: 6 5% 13: 6 5% 14: 6 5% 15: 6 5% 16: 6 5% 17: 6 5% 18: 6 5% 19: 6 5% 20: 6 5% 21: 6 5% 22: 5 4.166667% 23: 4 3.333333% 24: 3 2.5% 25: 2 1.666667% 26: 1 .8333334%
Tot: 120 |
d20+d8 1: 0% 2: 1 .625% 3: 2 1.25% 4: 3 1.875% 5: 4 2.5% 6: 5 3.125% 7: 6 3.75% 8: 7 4.375% 9: 8 5% 10: 8 5% 11: 8 5% 12: 8 5% 13: 8 5% 14: 8 5% 15: 8 5% 16: 8 5% 17: 8 5% 18: 8 5% 19: 8 5% 20: 8 5% 21: 8 5% 22: 7 4.375% 23: 6 3.75% 24: 5 3.125% 25: 4 2.5% 26: 3 1.875% 27: 2 1.25% 28: 1 .625%
Tot: 160 |
d20+d12 1: 0% 2: 1 .4166667% 3: 2 .8333334% 4: 3 1.25% 5: 4 1.666667% 6: 5 2.083333% 7: 6 2.5% 8: 7 2.916667% 9: 8 3.333333% 10: 9 3.75% 11: 10 4.166667% 12: 11 4.583333% 13: 12 5% 14: 12 5% 15: 12 5% 16: 12 5% 17: 12 5% 18: 12 5% 19: 12 5% 20: 12 5% 21: 12 5% 22: 11 4.583333% 23: 10 4.166667% 24: 9 3.75% 25: 8 3.333333% 26: 7 2.916667% 27: 6 2.5% 28: 5 2.083333% 29: 4 1.666667% 30: 3 1.25% 31: 2 .8333334% 32: 1 .4166667%
Tot: 240 |
d20+d20 1: 0% 2: 1 .25% 3: 2 .5% 4: 3 .75% 5: 4 1% 6: 5 1.25% 7: 6 1.5% 8: 7 1.75% 9: 8 2% 10: 9 2.25% 11: 10 2.5% 12: 11 2.75% 13: 12 3% 14: 13 3.25% 15: 14 3.5% 16: 15 3.75% 17: 16 4% 18: 17 4.25% 19: 18 4.5% 20: 19 4.75% 21: 20 5% 22: 19 4.75% 23: 18 4.5% 24: 17 4.25% 25: 16 4% 26: 15 3.75% 27: 14 3.5% 28: 13 3.25% 29: 12 3% 30: 11 2.75% 31: 10 2.5% 32: 9 2.25% 33: 8 2% 34: 7 1.75% 35: 6 1.5% 36: 5 1.25% 37: 4 1% 38: 3 .75% 39: 2 .5% 40: 1 .25%
Tot: 400 |
d20+2d20 1: 0% 2: 0% 3: 1 .0125% 4: 3 .0375% 5: 6 .075% 6: 10 .125% 7: 15 .1875% 8: 21 .2625% 9: 28 .35% 10: 36 .45% 11: 45 .5625% 12: 55 .6875% 13: 66 .825% 14: 78 .975% 15: 91 1.1375% 16: 105 1.3125% 17: 120 1.5% 18: 136 1.7% 19: 153 1.9125% 20: 171 2.1375% 21: 190 2.375% 22: 210 2.625% 23: 228 2.85% 24: 244 3.05% 25: 258 3.225% 26: 270 3.375% 27: 280 3.5% 28: 288 3.6% 29: 294 3.675% 30: 298 3.725% 31: 300 3.75% 32: 300 3.75% 33: 298 3.725% 34: 294 3.675% 35: 288 3.6% 36: 280 3.5% 37: 270 3.375% 38: 258 3.225% 39: 244 3.05% 40: 228 2.85% 41: 210 2.625% 42: 190 2.375% 43: 171 2.1375% 44: 153 1.9125% 45: 136 1.7% 46: 120 1.5% 47: 105 1.3125% 48: 91 1.1375% 49: 78 .975% 50: 66 .825% 51: 55 .6875% 52: 45 .5625% 53: 36 .45% 54: 28 .35% 55: 21 .2625% 56: 15 .1875% 57: 10 .125% 58: 6 .075% 59: 3 .0375% 60: 1 .0125%
Tot: 8000 |
d20+3d20 1: 0% 2: 0% 3: 0% 4: 1 .000625% 5: 4 .0025% 6: 10 .00625% 7: 20 .0125% 8: 35 .021875% 9: 56 .035% 10: 84 .0525% 11: 120 .075% 12: 165 .103125% 13: 220 .1375% 14: 286 .17875% 15: 364 .2275% 16: 455 .284375% 17: 560 .35% 18: 680 .425% 19: 816 .51% 20: 969 .605625% 21: 1140 .7125% 22: 1330 .83125% 23: 1540 .9625% 24: 1767 1.104375% 25: 2008 1.255% 26: 2260 1.4125% 27: 2520 1.575% 28: 2785 1.740625% 29: 3052 1.9075% 30: 3318 2.07375% 31: 3580 2.2375% 32: 3835 2.396875% 33: 4080 2.55% 34: 4312 2.695% 35: 4528 2.83% 36: 4725 2.953125% 37: 4900 3.0625% 38: 5050 3.15625% 39: 5172 3.2325% 40: 5263 3.289375% 41: 5320 3.325% 42: 5340 3.3375% 43: 5320 3.325% 44: 5263 3.289375% 45: 5172 3.2325% 46: 5050 3.15625% 47: 4900 3.0625% 48: 4725 2.953125% 49: 4528 2.83% 50: 4312 2.695% 51: 4080 2.55% 52: 3835 2.396875% 53: 3580 2.2375% 54: 3318 2.07375% 55: 3052 1.9075% 56: 2785 1.740625% 57: 2520 1.575% 58: 2260 1.4125% 59: 2008 1.255% 60: 1767 1.104375% 61: 1540 .9625% 62: 1330 .83125% 63: 1140 .7125% 64: 969 .605625% 65: 816 .51% 66: 680 .425% 67: 560 .35% 68: 455 .284375% 69: 364 .2275% 70: 286 .17875% 71: 220 .1375% 72: 165 .103125% 73: 120 .075% 74: 84 .0525% 75: 56 .035% 76: 35 .021875% 77: 20 .0125% 78: 10 .00625% 79: 4 .0025% 80: 1 .000625%
Tot: 160000 |