Some of the designers have provided size charts.  We have listed them here for your reference.
 

Sherri Hill Size Chart

45 inches from waist to floor.
SIZE
Bust
Waist
Hip
0
32 1/2
24
35 1/2
2
33 1/2
25
36 1/2
4
34 1/2
26
37 1/2
6
35 1/2
27
38 1/2
8
36 1/2
28
39 1/2
10
37 3/8
29
40 1/2
12
39
30 1/2
42
14
40 1/2
32
43 1/2
16
42
33 1/2
45
18
44
35 1/2
47

La Femme Size Chart

 
SIZE
Bust
Waist
Hip
0
33
25
36
2
34
26
37
4
35
27
38
6
36
28
39
8
37
29
40
10
38
30
41
12
40
32
43
14
42
34
45
16
44
36
47
18
46
38
49
   
 

Jovani Size Chart

SIZE
Bust
Waist
Hip
0
32
25 1.5
36
2
33
26 1/2
36 1/2
4
34
27 1/2
37 1/2
6
35
28 1/2
38 1/2
8
36
29 1/2
39 1/2
10
37
30 1/2
40 1/2
12
38 1/2
31 1/2
41 1/2
14
40
33 1/2
43 1/2
16
42
35
46
18
44
37
48
20
46
39 1/2
50
22
48 1/2
42
52
24
51
45
54
26
54
47
56
28
56
49
58
30
58
51
60
32
60
54
63
   
 

Faviana Size Chart

SIZE
Bust
Waist
Hip
XS or 0
31 1/2
23
35 1/2
XS or 1/2
32 1/5
24
36 1/2
S or 3/4
33 1/2
25
37 1/2
S or 5/6
34 1/2
26
38 1/2
M or 7/8
35 1/2
27
39 1/2
M or 9/10
36 1/2
28
40 1/2
L or 11/12
37 1/2
29
41 1/2
L or 13/14
38 1/2
30
42 1/2
XL or 15/16
40
31 1/2
44
17/18
42
33 1/2
46
19/20
44
35 1/2
48
21/22
46
37 1/2
50
23/24
48
39 1/2
52
   
 

Mori Lee Size Chart

SIZE
Bust
Waist
Hip

0

-
-
-
2
32
24
34
4
33
25
35
6
34
26
36
8
35
27
37
10
36
28
38
12
37 1/2
29 1/2
39 1/2

14

39
31
41
16
40 1/2
32 1/2
42 1/2
18
42
34
43 1/2
20
44
35 1/2
45
22
47 1/2
39
48
24
51 1/2
43
52
   
 

Scala Size Chart

SIZE
Bust
Waist
Hip
XS or 3/4
32
24
36
S or 5/6
33
25
37
M or 7/8
35
27
39
L or 9/10
37 1/2
29 1/2
41 1/2
XL or 11/12
39 1/2
31 1/2
43 1/2
XXL or 13/14
41 1/2
33
45
1X or 16
44 1/2
38 1/2
47
2X or 18
46 1/2
40 1/2
49
3X or 20
48 1/2
42 1/2
51
4X or 22
50 1/2
44 1/2
53
   
 

Niteline Size Chart

SIZE
Bust
Waist
Hip

0

31 1/2
25
35 1/2
2
32 1/2
26
36 1/2
4
33 1/2
27
37 1/2

6

34 1/2
28
38 1/2
8
35 1/2
29
39 1/2
10
36 1/2
30
40 1/2
12
38
31 1/2
42

14

39 1/2
33
43 1/2
16
41
34 1/2
45