You'll never buy ridiculous sunglasses again (no matter how fashionable).

Sunglasses are one of those items that are both practical – they were once an essential eye protector prescribed for medical purposes – and stylish. But why do some styles look so ridiculous on your face?

Like anything deemed “fashion”, sunglass styles have come and gone, with a few universally cringe-worthy styles here and there. Anyone else remember the bug-eyed craze of the mid-noughties? Dark, dark days.

Not surprisingly, the answer to finding the glass slipper of sunnies is face shape. So which sunglasses suit your face?

Square/rectangular

Your face is roughly the same length down as it is wide, with a particularly prominent jaw line and broad cheekbones. For all you square face gals out there, round sunnies are the best fit for you. Circular or warfarer shapes, with a round bottom edge, soften your squareness, yet compliment your bold features. You might want to avoid heavy or overpowering frames, which distract from your natural face traits.

Round

A round face means is nearly as wide as it is long, like those square faces out there, but without the prominent jaw line. It is also more of a circle than an oval. For this face type, frames with hard, rectangular lines and sunnies that are wider than they are deeper, will make your face appear thinner. Think of it like opposites attract. Try avoiding round sunnies, which will make your features seem larger. John Lennon frames are not for you.

Oval

An oval faced person will have balanced features, and the general rule is that the length of the face is one and a half times of the width. For all you lucky oval faced woman, any type of frame will suit you, so go nuts. Remember to compliment your features, so if you have a larger head, wear chunky glasses, and vice versa for those with smaller heads.

Heart

Heart shaped faces have wider foreheads and high cheekbones, and thin out to a pointed chin. The key is to choose a style that is no wider than your face, and is not too top heavy; this way it won’t over-emphasise your chin and will continue to complement those lovely cheekbones.

What face shape do you have? Let us know in the comments.

Like this? Why not try ...

Copy her look: 11 formidable women with gorgeous grey hair.

What your sleeping position says about your relationship.

The secret benefits of a bloody great belly laugh.