There is a magic formula to determine if you have droopy breasts. The perfect breast, according to a scientific study, has 45% volume at the top and 55% at the bottom. The nipple is above the breast crease and points slightly upwards.
If you have breasts with a nipple at the same level or lower than the breast fold, you are a basically suitable candidate for a breast lift.
The perfect breast does not take into account the cup volume of the breast. Small breasts can also be very beautiful. If you still want more volume then you can opt for a breast lift with implants.
For sagging breasts (grade 1 or more) - when the nipple is equal or lower than the fold under the breast - you are a suitable candidate for a breast lift.
Breast lift: do you have enough cup-filling, but is the skin of the breasts sagging? Then you are a good candidate to have your breasts firmed up by a breast lift.
Breast lift + Breast augmentation: do you have (too) little cup-filling and is the skin of your breasts sagging? Then you are a good candidate to have your breasts firmed up with a breast lift with implants.