We all know that 'size 10' can vary wildly in different shops. But until every brand cuts from the same template (never going to happen), a new online sizing programme may come to our rescue. What Size Am I, tells you what size will fit you best in different UK and US shops.
I enter my bust, waist and hip measurements and the site comes back with a list showing my top, skirt and dress size in various shops. Depressingly, it tells me my best fit on the high street is Monsoon.
As I suspected I'm a size eight at ASOS, Dorothy Perkins, Karen Millen, Monsoon, Oasis and Topshop but a size six at French Connection, Jaeger, LK Bennett, M&S, Next, New Look, Reiss, Warehouse, Whistles and Zara. At Gap and Banana Republic I'm a four (these two are sister shops).
I'm a fairly normal shape so it's surprising that I split the UK high street down the middle. I test out the site's suggestions in shops, and it's right every time, except in Gap where I prefer the look of size six to the site's recommended four.
[Related story: Surge in sales of 'Adele' size mannequins]
At Whistles, French Connection and Reiss assistants admit their sizes come up large, and a friend tells me that she can only wear Zara jackets because they're cut for a curvy, petite physique than most UK high street brands — which is better for her proportionally small waist.
Creator Anna Powell Smith has said she was surprised to find that more expensive shops tend to cut more generously. But if you bear in mind that cut is meant to reflect a brand's average customer it's no surprise that high street stores aimed at teenagers and young women tend to use a 'younger' body template which often translates to a more boyish silhouette.
By the same token, European brands will often cut to a more petite template than UK or US brands.
Powell Smith noticed that French Connection and Reiss cater to a more pear shaped figure, and Topshop and Oasis for a more 'straight up and down' physique. LK Bennett is good if you have a small waist in proportion to your hips.
[Related feature: How clothing sizes vary worldwide]
This would definitely be a handy app to have on your phone instead of lugging two of every size into a fitting room, and brilliant when buying online. It's a doddle to use and easy on the eye, and the only fiddly bit is taking your measurements in the first place.
It would be even better if trousers and jeans sizes were shown too.
Why did nobody think of it before? Powell Smith made the point that not many computer programmers are also into fashion. Guess it may be a while till we get a version for male shopaholics, then.