When you look at a rectangle face it is more than 1.5 times it’s width (and more than 3 noses long) but it has a square jaw and hairline. The sides are fairly straight

Great hairstyles for a rectangle face

You will want to make the face appear a little shorter and more balanced so you can do this by:

A fringe (bangs) either full to your eyebrows and straight or side swept
Width at the sides of your face, whether it’s layers, waves or curls they both work
When you wear your hair in a ponytail, if you don’t have a fringe, leave out some wisps of hair to soften your square jaw
Layered hair is your friend as it helps to give longer hair more volume
Curly haired rectangles can have longer hair as they naturally have more width with the curls, but keep layers in the cut so your curls have bounce
Slightly longer than jaw length bobs with a fringe work well for you
Short hair needs a fringe and it needs some softening pieces at the nape of your neck that distract from your jaw, otherwise it can look very masculine

Hairstyles to avoid for a rectangle face

You don’t want to add extra height or length to your face so avoid:

Fullness at the crown without volume at the side
Long straight hair parted in the middle
Avoid excessive length which will just make your face look longer
Short hair with volume on the top, none at the sides and no length around the neck.