Two people with the same chest size can differ in shoulder width, torso length, arm length and belly. Leather can’t be let out like cloth, because the needle holes stay. So we ask for seven measurements, adjust the pattern to all of them, and cut once.

Leather is less forgiving than cloth for three reasons. Every stitch punches a hole that stays if the seam is moved. Seam allowances are small, so there’s little to let out. And leather can’t be pressed or steamed into a new shape the way wool can. A leather jacket has to be cut to the right proportions the first time.

Chest size is only the starting point

A jacket can fit through the chest and still pull across the shoulders, hang too long through the torso, or end with sleeves that cover the hand. The jacket also has to be bigger than your body. That extra room is called ease, and how much you need depends on the style and what you wear underneath: a close racer jacket over a T-shirt needs less than a bomber over a sweater. That’s why we ask for your fit preference (slim, regular or relaxed), and for your waist or belly at its fullest point, so the front closes without pulling. The leather matters too. Lambskin is thin and soft, so it drapes and gives a little with wear. Cowhide is thicker and holds its shape, so the ease has to be right from the start.

Shoulders control more than shoulder width

The shoulder seam is where the sleeve hangs from, so it decides how the chest and sleeves fall and how the jacket moves when you reach. Too narrow, and the jacket pulls across your back and the sleeves feel short. Too wide, and the seam drops off your shoulder and the sleeve wrinkles below it. Shoulders are the hardest part of a leather jacket to alter afterward, so we ask for shoulder width, measured straight across the back from one shoulder seam to the other.

Sleeve pitch matters

Arms don’t hang straight down. They angle slightly forward, and patternmakers build that angle, called pitch, into the sleeve. The armhole matters too. A low, roomy armhole looks comfortable, but it makes the whole jacket lift when you reach forward. A higher armhole lets the arm move without dragging the body with it. Pitch and armhole are set by the pattern for each style. What you give us is sleeve length, measured from the shoulder seam down the outside of the arm to the end of the cuff, and cuff width, measured across a sleeve laid flat at the wrist.

Torso length changes the whole silhouette

A jacket designed for a long torso can swallow someone with the same chest size but shorter proportions. The opposite can expose the waist and make pockets sit too high. Length also depends on the style: a racer or biker jacket usually ends near the belt, while a field jacket sits lower. We ask for jacket length, from the highest point of the shoulder straight down to the hem, and hem width, so the bottom of the jacket clears your hips instead of riding up over them.

This is why we collect measurements before cutting

Once leather panels are cut, the material is committed, so cutting waits for your measurements. After you order, you submit seven: shoulder width, chest, waist or belly, hem width, jacket length, sleeve length and cuff width. You also choose cowhide or lambskin and a slim, regular or relaxed fit, and you can add photos of yourself or of a jacket that already fits. Several measurements can be taken from a jacket you like, laid flat. That copies a fit you know works, ease included. A fit specialist reviews every set before production, and the workshop adjusts the pattern to all of them.

What each measurement controls