The short answer. La DoubleJ runs true to size. The house sells most of its ready-to-wear in lettered sizing from XXS to XXL, keeps Italian numeric sizing for its tailored and structured pieces, and sells denim in inch waists. If you are usually a UK 10, you are an S in the lettered styles and an IT 42 in the numeric ones. Shop the full La DoubleJ collection at Luxury Shoes .
La DoubleJ is one of the few houses where the size label changes depending on what you are buying. A swing dress carries a letter, a Bijoux jacket carries an Italian number, and the jeans carry an inch waist. That is not inconsistency, it is a Milanese house applying the convention that suits each garment. Once you know which system you are in, the brand is straightforward to buy.
I went through the house’s current Spring Summer 2026 collection to see how it actually breaks down. The overwhelming majority of styles are lettered, a smaller group of tailored and structured pieces are Italian numeric, and a handful of capes, ponchos and kaftans are cut as one size. Nothing in the brand’s own product copy asks you to size up, and nothing asks you to size down.
The three systems La DoubleJ uses
1. Lettered sizing, XXS to XXL
This covers most of the house: the swing dresses, the silk tops, the jersey pieces, the kaftans and the printed separates. The cut is generous through the body by design, so the letter you wear elsewhere is the letter you wear here. La DoubleJ’s own models stand between 176cm and 180cm and wear a size S across the current season, which tells you the sample is cut long and easy rather than tight.
2. Italian numeric sizing, IT 38 to IT 48
The tailored and structured styles carry Italian numbers. Think the Bijoux jacket, the coats, the skirts with a fixed waist, the pieces that need to sit on the body rather than skim it. Luxury Handbags shows these on the UK ladder so you do not have to convert in your head, and the conversion is the standard Italian one: subtract 32 from the Italian number to get the UK size.
3. Denim in inch waists
The jeans, the Barrel, the Cropped Flare and the Tune Up Maven, are sold in inch waists from 23 to 34. Buy your usual denim waist. These are not vanity sized.
La DoubleJ size conversion
| Letter | UK | Italian (IT) | French (FR) | US |
|---|---|---|---|---|
| XXS | 4 | 36 | 32 | 0 |
| XS | 6 | 38 | 34 | 2 |
| S | 8 to 10 | 40 to 42 | 36 to 38 | 4 to 6 |
| M | 12 | 44 | 40 | 8 |
| L | 14 | 46 | 42 | 10 |
| XL | 16 | 48 | 44 | 12 |
| XXL | 18 | 50 | 46 | 14 |
Every Luxury Handbags product page carries the exact size selector for that style, so check the piece itself before ordering.
How the main shapes fit
- The Swing Dress. The house signature, cut slim through the shoulder and generous through the hip, falling into an A-line. It is the most forgiving thing La DoubleJ makes. Take your usual letter. More on the family in the swing dress guide.
- Kaftans and ponchos. Often one size, cut wide and meant to hang. There is nothing to fit.
- Tailoring and jackets. Italian numeric, cut closer. If you are between sizes and want to wear a knit underneath, this is the one place I would take the larger number.
- Skirts with a fixed waist. The Pencil Skirt and the structured styles sit low on the waist and hem around the calf. Go by your waist measurement, not your dress size.
- Jersey and knit. Stretch does the work. Your usual letter, and no need to size up for comfort.
Three things worth knowing before you order
The prints are placed, so the size changes the picture. On a placed print the motif is positioned for each size, which is why a Placée style photographs slightly differently across the range. It is deliberate, and it is one of the reasons these dresses are cut in Italy rather than graded automatically.
Length is consistent, not adjustable. A La DoubleJ maxi sits long. The house publishes a garment length in centimetres on most styles, and at 165cm and under a maxi will graze the floor. Worth a shortening if you want to wear it flat.
Italian numeric runs the same as other Milanese houses. If you know your Italian size in Dolce and Gabbana, it carries across.
Frequently asked questions
Does La DoubleJ run true to size?
Yes. La DoubleJ runs true to size and publishes no sizing correction on its ready-to-wear. The cut is relaxed and Italian, generous through the hip on the swing shapes and closer on the tailoring, so take your usual size in whichever system the piece uses.
What size is a La DoubleJ S in UK sizing?
A La DoubleJ S covers a UK 8 to a UK 10, which is an Italian 40 to 42. The house cuts its lettered styles with ease, so an S carries a UK 10 comfortably on the swing and kaftan shapes.
Why do some La DoubleJ pieces use letters and others use numbers?
The house uses lettered sizing for its relaxed styles, the swing dresses, kaftans, silk tops and jersey, and Italian numeric sizing for tailored and structured pieces such as jackets, coats and fitted skirts. Denim is sold separately in inch waists.
How do I convert La DoubleJ Italian sizing to UK?
Subtract 32 from the Italian number. An IT 40 is a UK 8, an IT 42 is a UK 10, an IT 44 is a UK 12 and an IT 46 is a UK 14. Luxury Handbags shows La DoubleJ numeric styles on the UK ladder already.
What size does the La DoubleJ model wear?
Across the current Spring Summer 2026 season the models stand between 176cm and 180cm and wear a size S, which is a useful reference for how long the house cuts its dresses.
Is La DoubleJ made in Italy?
Yes. La DoubleJ is made in Italy, working with historic Milanese and Lake Como textile mills. There is more on the making in where La DoubleJ is made.
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