Men's underwear has a simple size system – from S to 4XL – and one common mistake: choosing a size by eye, based on your T-shirt. Boxers and briefs are sized by your waist where the waistband sits and by your hip circumference. Below: the manufacturer's chart, how to measure and rules for each style.
How to measure your waist and hips
- Waist: run a tape measure horizontally around your body at the height where you wear the waistband – for most men just below the navel. Do not pull your stomach in; the tape should sit flat, not squeeze.
- Hips: horizontally around the widest part of your buttocks.
- Write down both results. If they point to two different sizes, the larger one decides.
Key men's underwear size chart
The chart of Key, the brand behind most of the boxers and briefs at Zeprado. Body measurements in centimetres:
| Size | Waist | Hips | Chest | Height |
|---|---|---|---|---|
| M | 86–90 | 103–107 | 96–100 | 170–176 |
| L | 90–94 | 107–111 | 100–104 | 176–182 |
| XL | 94–98 | 111–115 | 104–108 | 182–188 |
| XXL (2XL) | 98–102 | 115–119 | 108–112 | 182–188 |
| 3XL | 102–106 | 119–123 | 112–116 | 176–182 |
| 4XL | 106–110 | 123–127 | 116–120 | 176–182 |
For boxers and briefs, waist and hips are what counts – chest and height do not affect the size. 2XL and XXL are the same size written two ways; both appear in our catalogue. Size S is available from brands such as Kappa, Sergio Tacchini and Exes. Their charts, and Henderson's, shift the limits by a few centimetres, so every product follows its own manufacturer's chart.
Boxers, briefs and long-leg boxers
- Fitted boxers (with legs) – the most sensitive to size. Too small and the legs roll up and dig into the thigh; too big and they bunch under trousers. Between sizes, choose the larger one: the leg lies flat in a larger size and rides up in a smaller one.
- Briefs – size by waist. The waistband should hold on the hips without leaving a mark; if a clear line remains after you take them off, the size is too small, not “the waistband too tight”.
- Long-leg boxers – for tall men and for wearing under a suit; the leg does not roll up when you walk. The size is chosen the same way, and we give the leg length in the product description: in the Key MXM 017 model it is about 30 cm.
- Loose boxers (shorts) – the most forgiving; use the size from the chart without adjustments.
Between two sizes
- Waist at the limit, hips in the larger size – take the larger one.
- Cotton with elastane (e.g. 95% and 5%) may shrink slightly when washed hot; if you are at the top of a range, choose the larger size.
- In 2- and 3-packs the size you choose applies to every piece in the pack.
Signs of the wrong size
- Too small: the waistband marks your stomach, the legs roll up when you sit, the side seams pull, there is not enough room at the crotch.
- Too big: the fabric bunches under trousers, the waistband slides down when you bend, the legs twist on the thigh.
Fabric content and care symbols are explained in how to read an underwear label. Fitted, loose and long-leg styles are in the men's boxers and men's briefs collections, and Key has the most styles in 3XL and 4XL. To complete the set: socks for a suit and men's pyjamas.