Fudge Dice

Probability [exact] is the probability of the dice summing to that value.
Probability [success] is the probability of the dice summing to that value or a higher value i.e. the probability of success if that dice roll was the target i.e. minimum value for success.

Roll	Probability [exact] (/81)	Probability [success] (/81)
+4	1	1
+3	4	5
+2	10	15
+1	16	31
0	19	50
-1	16	66
-2	10	76
-3	4	80
-4	1	81

Roll	Probability [exact] (%)	Probability [success] (%)
+4	1.23	1.23
+3	4.94	6.17
+2	12.34	18.52
+1	19.75	38.27
0	23.46	61.73
-1	19.75	81.48
-2	12.34	93.83
-3	4.94	98.77
-4	1.23	100.00