Why this is the most versatile hair cut - whether you're in your 30s or 50s

There may be 23 years between them, but Margot Robbie, 29, and Nicole Kidman, 52, are currently sporting the same mid-length hair style in equal brilliance
There may be 23 years between them, but Margot Robbie, 29, and Nicole Kidman, 52, are currently sporting the same mid-length hair style in equal brilliance Credit:  FilmMagic/Axelle/Bauer-Griffin

Last week, Margot Robbie, 29, and Nicole Kidman, 52, hit the US talk show circuit, alongside co-star Charlize Theron, to promote their highly anticipated film Bombshell (due to hit UK cinemas in January) about three female employees at Fox News who take on a toxic male culture.

While there are 23 years between them, both Robbie and Kidman are sporting the same mid-length hair style - right down to the hair parting, length and texture, proving that a darn good haircut is still the smartest way to look ageless. Who needs filler or Botox when you've got the name of a top celebrity hairdresser?

Sitting a few inches below the shoulder with no blunt fringe or obvious layers to speak of, while this may look like an unassuming hairstyle, its hidden details are what make it so flattering - on any age, hair type or face shape. Hair stylist Michael Van Clarke says mid length cuts are flattering for all women and shouldn't be overlooked as 'plain' or 'safe'. Unlike very long hair that can sometimes pull the face downwards, opting for a mid length 'takes the weight off of hair, creating more lift at the roots which in turn lifts the face,' he says. 

And they're not the only celebrities enjoying this classic hair do. Carrie Symmonds, the Duchess of Cambridge, Cheryl Cole and Jennifer Aniston all stay looking youthful - and contemporary - with their not-too-long, not-too-short hair cut.

The thing that makes this length so ageless is its versatility. Being low maintenance enough for everyday but classic enough to accompany an evening cocktail dress, because of the subtle elements of this cut, it can be worn loose and textured like Margot Robbie or glossy and bouncy like the Duchess of Cambridge. While Jennifer Aniston's shiny, straight interpretation shows that with a few face framing layers, you can not only make your hair appear more voluminous, you can soften your facial features. 

The four key details that make the new mid-length so ageless 

1. A centre parting will frame and sculpt the face 

Match made in heaven: A centre parting and the mid length cut compliment each other perfectly 

A centre parting and the mid length cut are made for each other. Not only does a centre parting look strong and confident, it can give height to the forehead (great for those with a shallow forehead like Jennifer Aniston) which opens up the face, it will frame the face and accentuate the cheekbones, Van Clarke says. 

A middle parting can restore the symmetry that our faces lose as we age  Credit: Jeff Kravitz /FilmMagic, Inc 

You can also create symmetry and balance with a middle parting. In fact, our faces become increasingly asymmetrical as we age due to years of sleeping on one side, so parting the hair in the middle restores this balance and evens out facial features.

2. It has layers in all the right places 

Adding layers to your style is the best way to give shape and definition to your look  Credit: Steve Granitz /WireImage 

One of the best ways to give shape and definition to the hair is to add layers. Hair that is all one length can often sit flat on the face and drag it down, accentuating jowls and droopy eyes but a few layers can give limp and lifeless looking hair the lift and bounce its needs. This is beneficial for those with fine hair as well as those who want to perk up a fading complexion. Indeed, a few strategically placed layers that sit just around the jaw line will lift the whole face. 

Mark Smith, Creative Director at John Frieda Salons recommends layering the hair from underneath to add movement and texture. By simply adding a long cheek-skimming fringe or pieces around the sides, it will draw attention to the eyes and soften facial features. Jennifer Aniston's glossy mid length cut is a great example of how youthful layers can be. 

3. A blunt base line gives the illusion of healthier, thicker hair

Opting for a blunt cut isn't just visually pleasing, it also takes years off your look

As we age and our estrogen levels drop, our hair can become thinner and lose volume, adding years to our appearance. While layers around the face can create structure  to one's facial features, by contrast, cutting the base line of your hair into a blunt, straight edge can transform the overall look and health of your hair. A blunt base line as seen on the Duchess of Cambridge, tidies up scraggly ends and makes hair appear thicker and more youthful.

4. Natural texture gives the mid length a young, carefree vibe 

No matter your texture, the new mid length cut can be embraced by all  Credit:  Axelle/Bauer-Griffin/ FilmMagic

One of the best things about the new mid length cut is that it works well with all textures from straight to wavy and curly. One of the reasons for this is its 'just-right' length. While curly or wavy hair can make a round face look even wider (if you've got a bob, for instance) mid length styles have just enough length to carry off that added texture without weighing waves down.

'Texture - as opposed to super straight, flat hair - always adds an element of youth to your look,' explains Smith. 'Waves have a lightness and movement about them that creates more fluidity. While light shows through the bends in the hair, which can brighten and lift the face for a more youthful look,' adds Smith.