HER unique style has inspired the ‘Kate Effect’, with millions of women throughout the world trying to copy her look.

And last week the US magazine Vanity Fair declared that the Duchess of Cambridge had topped their best-dressed list for a third time, making the Royal fashion icon their September cover girl.

Now, a Mail on Sunday survey of outfits worn by the Duchess in the past two years has revealed the secrets of her wardrobe. And occasional criticism of her ‘drab’ taste in colours is proved ill-founded as the Duchess emerges as Kaleidoscope Kate.

Like the Queen, Kate’s favourite hue is Royal blue, making up 21 per cent of her colour choices. Yes, she also likes a neutral look, wearing white and cream 16 per cent of the time and grey another 16 per cent of the time.

But she also goes for bold colours, opting for stark black and white combinations nine per cent of the time, pink eight per cent and red seven per cent.

Green is her colour choice nine per cent of the time, purple and black four per cent each, while she has worn brown or yellow on three per cent of occasions each.

But blue is without doubt her favourite. Kate wore a sapphire jersey dress by Brazilian fashion house Issa for her famous engagement interview and a cobalt blue dress from high street store Zara for her going-away outfit the morning after the Royal Wedding.

And when she made her first-ever speech in East Anglia earlier this year, she opted for a Royal blue dress from Reiss.

Kate refuses to hire a personal stylist and has been dubbed the Duchess of Thrift because of her habit of recycling her outfits and buying high street frocks, making her style seem more accessible for her myriad admirers.

And despite her splashes of colour, the Duchess has made nude tones a trademark. From cream through to champagne, blush and white - a colour she recently wore to Wimbledon in the form of an elegant Ralph Lauren dress - neutrals account for 32 per cent of her wardrobe. The £185 neutral Sledge platform court shoes she has from high street store LK Bennett are her trusted choice of footwear.

Kate recycled an elegant white military-style Alexander McQueen coat dress for the Order of the Garter Service in Windsor in June and set the tone - the Duchess of Cornwall and the Countess of Wessex echoed her look in elegant neutral colours and cream court shoes.  –DM

But, like the Queen, Kate knows how to use colour to send out a message.

In Ottawa on Canada Day she thrilled crowds by dressing in the national colours of red and white and, for an Olympic exhibition at the National Portrait Gallery last month, she wore a brilliant blue crepe dress by British designer Stella McCartney, who designed Team GB’s kit.

When she visited the Irish Guards on St Patrick’s Day, Kate experimented with an emerald green coat dress by designer Emilia Wickstead.

But although the Duchess has become bolder with colour, grey remains an important part of her £100,000 wardrobe, which is financed largely by the Prince of Wales. Last week for a reception at the Royal Academy of Arts, she wore an elegant, dove-grey cocktail dress by Serbian-born designer Roksanda Ilincic.

The colour may have been deemed drab by some, but Kate’s choice of a cutting-edge designer highlights exactly why she’s the world’s most colourful style icon.              –DM