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User talk:LRichardson/Essays/2d6 to 1d20 Conversion

I'm going to be reworking this to include equivalences for 1d20, 1d24, 1d30 and 1d100.

In the meantime I am going to be holding the formatted tables here.

Table Holding Area[edit]

2d6[edit]

Decimal Values
Roll P equal to or P less P equal to or P greater
( R ) less than R than R greater than R than R
2 0.0278 0.0000 1.0000 0.9722
3 0.0833 0.0278 0.9722 0.9167
4 0.1667 0.0833 0.9167 0.8333
5 0.2778 0.1667 0.8333 0.7222
6 0.4167 0.2778 0.7222 0.5833
7 0.5833 0.4167 0.5833 0.4167
8 0.7222 0.5833 0.4167 0.2778
9 0.8333 0.7222 0.2778 0.1667
10 0.9167 0.8333 0.1667 0.0833
11 0.9722 0.9167 0.0833 0.0278
12 1.0000 0.9722 0.0278 0.0000


Reduced Table
Roll Number of C equal to or C less C equal to or C greater
( R ) Combinations less than R than R greater than R than R
2 1 1 0 36 35
3 2 3 1 35 33
4 3 6 3 33 30
5 4 10 6 30 26
6 5 15 10 26 21
7 6 21 15 21 15
8 5 26 21 15 10
9 4 30 26 10 6
10 3 33 30 6 3
11 2 35 33 3 1
12 1 36 35 1 0


1d20[edit]

1d20
Roll P equal to or P less P equal to or P greater
( R ) less than R than R greater than R than R
1 0.05 0.00 1.00 0.95
2 0.10 0.05 0.95 0.90
3 0.15 0.10 0.90 0.85
4 0.20 0.15 0.85 0.80
5 0.25 0.20 0.80 0.75
6 0.30 0.25 0.75 0.70
7 0.35 0.30 0.70 0.65
8 0.40 0.35 0.65 0.60
9 0.45 0.40 0.60 0.55
10 0.50 0.45 0.55 0.50
11 0.55 0.50 0.50 0.45
12 0.60 0.55 0.45 0.40
13 0.65 0.60 0.40 0.35
14 0.70 0.65 0.35 0.30
15 0.75 0.70 0.30 0.25
16 0.80 0.75 0.25 0.20
17 0.85 0.80 0.20 0.15
18 0.90 0.85 0.15 0.10
19 0.95 0.90 0.10 0.05
20 1.00 0.95 0.05 0.00


1d20
Roll Raw 2d6 Adjusted Wildcard Alt. Wildcard
( R ) Equivalent 2d6 Eq. 2d6 Eq. 2d6 Eq.
1 2 2 3 3
2 3 3 4 4
3 4 4 4 4
4 5 5 5 5
5 5 5 5 5
6 5 6 6 6
7 6 6 6 6
8 6 6 6 7
9 7 7 7 7
10 7 7 7 7
11 7 7 7 7
12 7 7 8 7
13 8 8 8 8
14 8 8 8 8
15 9 8 9 9
16 9 9 9 9
17 9 9 10 10
18 10 10 10 10
19 11 11 11 11
20 12 12 2 or 12 2 or 12

1d24[edit]

Decimal Probability[edit]

1d24
Roll P equal to or P less P equal to or P greater
( R ) less than R than R greater than R than R
1 0.0417 0.0000 1.0000 0.9583
2 0.0833 0.0417 0.9583 0.9167
3 0.1250 0.0833 0.9167 0.8750
4 0.1667 0.1250 0.8750 0.8333
5 0.2083 0.1667 0.8333 0.7917
6 0.2500 0.2083 0.7917 0.7500
7 0.2917 0.2500 0.7500 0.7083
8 0.3333 0.2917 0.7083 0.6667
9 0.3750 0.3333 0.6667 0.6250
10 0.4167 0.3750 0.6250 0.5833
11 0.4583 0.4167 0.5833 0.5417
12 0.5000 0.4583 0.5417 0.5000
13 0.5417 0.5000 0.5000 0.4583
14 0.5833 0.5417 0.4583 0.4167
15 0.6250 0.5833 0.4167 0.3750
16 0.6667 0.6250 0.3750 0.3333
17 0.7083 0.6667 0.3333 0.2917
18 0.7500 0.7083 0.2917 0.2500
19 0.7917 0.7500 0.2500 0.2083
20 0.8333 0.7917 0.2083 0.1667
21 0.8750 0.8333 0.1667 0.1250
22 0.9167 0.8750 0.1250 0.0833
23 0.9583 0.9167 0.0833 0.0417
24 1.0000 0.9583 0.0417 0.0000


2d6 Equivalences[edit]

1d24
Roll Raw 2d6 Adjusted Wildcard Alt. Wildcard
( R ) Equivalent 2d6 Eq. 2d6 Eq. 2d6 Eq.
1 2 2 3 3
2 3 3 4 4
3 4 4 4 4
4 4 4 5 5
5 5 5 5 5
6 5 5 5 6
7 5 5 6 6
8 6 6 6 6
9 6 6 6 6
10 6 6 7 7
11 7 7 7 7
12 7 7 7 7
13 7 7 7 7
14 7 7 7 7
15 8 8 8 8
16 8 8 8 8
17 8 8 8 8
18 9 9 9 8
19 9 9 9 9
20 9 9 9 9
21 10 10 10 10
22 10 10 10 10
23 11 11 11 11
24 12 12 2 or 12 2 or 12


Battlemech Hit Location Table[edit]

Adjusted[edit]

1d24 Left Front / Rear Right
1 Left Torso (Crit) Center Torso (Crit) Right Torso (Crit)
2 Left Leg Right Arm Right Leg
3 Left Arm Right Arm Right Arm
4 Left Arm Right Arm Right Arm
5 Left Arm Right Leg Right Arm
6 Left Arm Right Leg Right Arm
7 Left Arm Right Leg Right Arm
8 Left Leg Right Torso Right Leg
9 Left Leg Right Torso Right Leg
10 Left Leg Right Torso Right Leg
11 Left Torso Center Torso Right Torso
12 Left Torso Center Torso Right Torso
13 Left Torso Center Torso Right Torso
14 Left Torso Center Torso Right Torso
15 Center Torso Left Torso Center Torso
16 Center Torso Left Torso Center Torso
17 Center Torso Left Torso Center Torso
18 Right Torso Left Leg Left Torso
19 Right Torso Left Leg Left Torso
20 Right Torso Left Leg Left Torso
21 Right Arm Left Arm Left Arm
22 Right Arm Left Arm Left Arm
23 Right Leg Left Arm Left Leg
24 Head Head Head


Wildcard[edit]

1d24 Left Front / Rear Right
1 Left Leg Right Arm Right Leg
2 Left Arm Right Arm Right Arm
3 Left Arm Right Arm Right Arm
4 Left Arm Right Leg Right Arm
5 Left Arm Right Leg Right Arm
6 Left Arm Right Leg Right Arm
7 Left Leg Right Torso Right Leg
8 Left Leg Right Torso Right Leg
9 Left Leg Right Torso Right Leg
10 Left Torso Center Torso Right Torso
11 Left Torso Center Torso Right Torso
12 Left Torso Center Torso Right Torso
13 Left Torso Center Torso Right Torso
14 Left Torso Center Torso Right Torso
15 Center Torso Left Torso Center Torso
16 Center Torso Left Torso Center Torso
17 Center Torso Left Torso Center Torso
18 Right Torso Left Leg Left Torso
19 Right Torso Left Leg Left Torso
20 Right Torso Left Leg Left Torso
21 Right Arm Left Arm Left Arm
22 Right Arm Left Arm Left Arm
23 Right Leg Left Arm Left Leg
24 Special Special Special


Alternate Wildcard[edit]

1d24 Left Front / Rear Right
1 Left Leg Right Arm Right Leg
2 Left Arm Right Arm Right Arm
3 Left Arm Right Arm Right Arm
4 Left Arm Right Leg Right Arm
5 Left Arm Right Leg Right Arm
6 Left Leg Right Torso Right Leg
7 Left Leg Right Torso Right Leg
8 Left Leg Right Torso Right Leg
9 Left Leg Right Torso Right Leg
10 Left Torso Center Torso Right Torso
11 Left Torso Center Torso Right Torso
12 Left Torso Center Torso Right Torso
13 Left Torso Center Torso Right Torso
14 Left Torso Center Torso Right Torso
15 Center Torso Left Torso Center Torso
16 Center Torso Left Torso Center Torso
17 Center Torso Left Torso Center Torso
18 Center Torso Left Torso Center Torso
19 Right Torso Left Leg Left Torso
20 Right Torso Left Leg Left Torso
21 Right Arm Left Arm Left Arm
22 Right Arm Left Arm Left Arm
23 Right Leg Left Arm Left Leg
24 Special Special Special


Special Result Table[edit]

1d24 Left Front / Rear Right
1 – 12 Head Head Head
13 – 24 LT (Critical) CT (Critical) RT (Critical)


Equivalent Cluster Hits Table[edit]

1d24 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 40
1 1 1 1 1 2 2 3 3 3 4 4 4 5 5 5 5 6 6 6 7 7 7 8 8 9 9 9 10 10 12
2 1 1 2 2 2 2 3 3 3 4 4 4 5 5 5 5 6 6 6 7 7 7 8 8 9 9 9 10 10 12
3 1 1 2 2 3 3 4 4 4 5 5 5 6 6 7 7 8 8 9 9 9 10 10 10 11 11 11 12 12 18
4 1 1 2 2 3 3 4 4 4 5 5 5 6 6 7 7 8 8 9 9 9 10 10 10 11 11 11 12 12 18
5 1 2 2 3 3 4 4 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
6 1 2 2 3 3 4 4 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
7 1 2 2 3 3 4 4 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
8 1 2 2 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
9 1 2 2 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
10 1 2 2 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
11 1 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
12 1 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
13 1 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
14 1 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
15 2 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
16 2 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
17 2 2 3 3 4 4 5 5 6 7 8 8 9 9 10 10 11 11 12 13 14 15 16 16 17 17 17 18 18 24
18 2 2 3 4 5 6 6 7 8 9 10 11 11 12 13 14 14 15 16 17 18 19 20 21 21 22 23 23 24 32
19 2 2 3 4 5 6 6 7 8 9 10 11 11 12 13 14 14 15 16 17 18 19 20 21 21 22 23 23 24 32
20 2 2 3 4 5 6 6 7 8 9 10 11 11 12 13 14 14 15 16 17 18 19 20 21 21 22 23 23 24 32
21 2 3 3 4 5 6 6 7 8 9 10 11 11 12 13 14 14 15 16 17 18 19 20 21 21 22 23 23 24 32
22 2 3 3 4 5 6 6 7 8 9 10 11 11 12 13 14 14 15 16 17 18 19 20 21 21 22 23 23 24 32
23 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 40
24 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 40

Base to Hit Tables[edit]

Direct Equivalent[edit]

Range To Hit Modifier
Short 4 0
Medium 9 5
Long 18 14


Shifted Values[edit]

Range To Hit Modifier
Short 4 0
Medium 10 6
Long 18 14

1d30[edit]

1d30
Roll P equal to or P less P equal to or P greater
( R ) less than R than R greater than R than R
1 0.0333 0.0000 1.0000 0.9667
2 0.0667 0.0333 0.9667 0.9333
3 0.1000 0.0667 0.9333 0.9000
4 0.1333 0.1000 0.9000 0.8667
5 0.1667 0.1333 0.8667 0.8333
6 0.2000 0.1667 0.8333 0.8000
7 0.2333 0.2000 0.8000 0.7667
8 0.2667 0.2333 0.7667 0.7333
9 0.3000 0.2667 0.7333 0.7000
10 0.3333 0.3000 0.7000 0.6667
11 0.3667 0.3333 0.6667 0.6333
12 0.4000 0.3667 0.6333 0.6000
13 0.4333 0.4000 0.6000 0.5667
14 0.4667 0.4333 0.5667 0.5333
15 0.5000 0.4667 0.5333 0.5000
16 0.5333 0.5000 0.5000 0.4667
17 0.5667 0.5333 0.4667 0.4333
18 0.6000 0.5667 0.4333 0.4000
19 0.6333 0.6000 0.4000 0.3667
20 0.6667 0.6333 0.3667 0.3333
21 0.7000 0.6667 0.3333 0.3000
22 0.7333 0.7000 0.3000 0.2667
23 0.7667 0.7333 0.2667 0.2333
24 0.8000 0.7667 0.2333 0.2000
25 0.8333 0.8000 0.2000 0.1667
26 0.8667 0.8333 0.1667 0.1333
27 0.9000 0.8667 0.1333 0.1000
28 0.9333 0.9000 0.1000 0.0667
29 0.9667 0.9333 0.0667 0.0333
30 1.0000 0.9667 0.0333 0.0000


1d30
Roll Raw 2d6 Adjusted Wildcard
( R ) Equivalent 2d6 Eq. 2d6 Eq.
1 2 2 3
2 3 3 3
3 3 3 4
4 4 4 4
5 4 4 4
6 5 5 5
7 5 5 5
8 5 5 5
9 6 6 6
10 6 6 6
11 6 6 6
12 6 6 6
13 6 7 7
14 7 7 7
15 7 7 7
16 7 7 7
17 7 7 7
18 8 7 8
19 8 8 8
20 8 8 8
21 8 8 8
22 8 8 9
23 9 9 9
24 9 9 9
25 9 9 10
26 10 10 10
27 10 10 10
28 11 11 11
29 11 11 11
30 12 12 2 or 12

1d100[edit]

1d100 Raw 2d6
Equivalent
2 1 - 3
3 4 - 8
4 9 - 17
5 18 - 28
6 29 - 42
7 43 - 58
8 59 - 72
9 73 - 83
10 84 - 92
11 93 - 97
12 98 - 100