This chart will help you determine the correct size to fit your body measurements. Please note, measurements may vary for some brands, but you may still use this as a guide.

PDI Loungewear Jogger Long Ladies Loungepants

Bust / Chest: Measure from under the armpits and across the widest part of the chest.
Waist: Measure your natural waistline, over the navel. Make sure the tape is loose and not too tight.
Hip: Measure across the widest part of the buttocks, 20cm down from your natural waistline.