If your part number starts with FW:

ITEM SIZE HEIGHT WEIGHT WAIST CHEST

Baby Bunting

One Size
Up to 25" Up to 18 Lbs - -
Infant 6 to 18 Months Up to 26" Up to 26 Lbs - -
Toddler
12- 24 Months
18 to 24 Months
up to 24 Months
24 Months to 2T
3T to 4T
24" to 28"
33' to 37"
28" to 31"
Up to 32"
33" to 35"
Up to 28 Lbs
Up to 28 Lbs
Up to 28 Lbs
Up to 30 Lbs
Up to 36 Lbs
-
18" to 20"
-
-
-
-
20" to 22"
-
-
-
Children
Small 4-6
Medium 8-10
Large 12-14
39" to 46"
49" to 54"
55" to 60"
35 to 45 Lbs
55 to 73 Lbs
74 to 100 Lbs
19" to 22"
23 to 25"
24" to 26"
20" to 23"
22" to 25"
27" to 30"
Teen
Juniors 0-9 4'-11" to 5'-6" 95 to 130 Lbs 24" to 27" 30" to 34"
Women
Sm/ Med 2 to 8
Med/Lg 8 to 14
One Size/Standard
5' to 5'-6"
5'-6" to 5'-11"
5'-2" to 5'-11"
100 to 135 Lbs
135 to 170 Lbs
105 to 170 Lbs
24" to 27"
28" to 33"
25" to 33"
32" to 36 1/2"
36" to 40"
32" to 40"
Men One Size
5'-6" to 6' 140 to 200 Lbs 25" to 38" 33" to 45"
Women Plus 16 to 24
5'-5" to 5'-11" - 32" to 42" 39" to 48"
Men Plus -
5'-9" to 6'-3" up to 300 Lbs 42" to 46" 48" to 53"

PET Costumes:
XSmall: 8"-10" from neck to tail base.
( Toy Poodle, Maltese, Shih Tzu)
Small: 11"-14" from neck to tail base.
( Cats, Yorkies, Pugs, Jack RuSell)
Medium: 15"-22" from neck to tail base,
( Beagles, Cocker Spaniels, Shelties)
Large: 22"-28 from neck to tail base,
( Labs, Boxers, Dobermans)
X Large: 28"+ from neck to tail base
Universal Women's Dress Size Conversion Chart
This is only a guide if the manufacture lists measurements in inches use that.

U.S. U.S. (letter sizes) U.K. France

Select the size in your country and note the US sizing.
Germany Italy Australia Japan