For trousers you need seven measurements: waist, hip, rise (the crotch length from front waist to back waist), inseam, outseam, thigh and height. Take them standing naturally in close-fitting clothes, with a soft tape held level and snug but not tight, over a string tied around your natural waist so every length starts from the same place. Write each down to the nearest 0.5 cm (1/4 in) and measure twice if two readings disagree.
What do you need before you measure?
A soft tape measure, a piece of string or narrow elastic to tie around your waist, a full-length mirror, and a pen. A second person makes the rise and outseam easier, but each one can be taken without help. Wear what you will wear under the trousers, and decide now whether you will measure barefoot or in the shoes you will wear with them: the inseam and outseam change by the heel height.
Tie the string around your natural waist, the narrowest part of your torso, usually just above the navel. Bend sideways: the crease that forms is your waist. The string will settle there and stay put, which is why it is worth the trouble.
Which measurements do trousers need?
| Measurement | Where | What it decides |
|---|---|---|
| Waist | Around the natural waist, at the string | Waistband length, dart intake |
| Hip | Around the fullest part of the seat, feet together | Width of the trouser at the hip, the crotch curve |
| Rise (crotch length) | From the string at center front, between the legs, to the string at center back | Total length of the front and back crotch curves |
| Crotch depth | Seated, from the string at the side down to the chair seat | How far down the crotch point sits |
| Thigh | Around the fullest part of one thigh | Leg width at the top |
| Inseam | From the crotch to the hem, along the inside of the leg | Leg length |
| Outseam | From the string at the side to the hem, along the outside of the leg | Leg length including the rise |
| Height | Standing against a wall, barefoot | Proportions and the default lengths |
The body measurements page shows where each one sits on a figure; the guide to taking body measurements covers the full set for every garment.
How do you measure your waist and hip for trousers?
Waist. Run the tape around the string, level all the way round, and read it with the tape snug against the body and your stomach relaxed. Do not breathe in. If you plan to wear the trousers lower than the natural waist, measure there as well and note where it is: so many centimeters below the string. Patterns are drafted from the natural waist and shaped down from it, so the natural waist is the number to give; the second number tells you where to cut the waist.
Hip. Stand with your feet together and find the fullest part of your seat in the mirror, side on. It is often lower than you expect, 18 to 23 cm (7 to 9 in) below the waist. Run the tape around at that level, check it is horizontal at the back, and read it without pulling. If your thighs are fuller than your seat, measure around the thighs at the top as well and use the larger number as the hip.
How do you measure the rise?
The rise is the length of the seam that runs from the front waist, under the body, to the back waist. Hold the tape end at the string at center front, pass it between your legs without pulling it into the body, and bring it up to the string at center back. Stand upright. Note the total, and also where the tape passes the midpoint between your legs, so you know the front rise and the back rise separately: the back is longer than the front by 5 to 8 cm (2 to 3 1/8 in) on most people, more with a full seat.
Crotch depth is a different thing: how far below the waist the crotch point sits. Sit on a flat, hard chair, upright, and measure down the side from the string to the chair seat. Add 1 to 2.5 cm (3/8 to 1 in) of ease for sitting comfort. Crotch depth versus crotch length explains why a pattern needs both and what goes wrong when one is off.
How do you measure the inseam and outseam?
Inseam. Stand with your feet about 15 cm (6 in) apart. Hold the tape at the top of the inside of one leg, as high as it can go without pulling, and run it down to where you want the hem: the ankle bone for a full-length trouser, the floor minus 2 cm (3/4 in) with shoes on for a trouser that breaks on the shoe. This one is easier to take from a pair of trousers that fit well and sit at the right length: lay them flat, smooth the inside leg seam and measure from the crotch seam to the hem.
Outseam. From the string at the side of the waist, straight down the outside of the leg over the hip, to the same hem point. Outseam minus inseam should equal your crotch depth, give or take a centimeter, which is a good check on all three.
How do you measure the thigh?
Run the tape around the fullest part of one thigh, usually 2 to 5 cm (3/4 to 2 in) below the crotch, with your weight on both feet. Keep the tape level, not angled up at the back. For tapered trousers add the knee, around the kneecap with the leg straight, and the calf, around the fullest part, so the leg can be narrowed without binding. Pull-on trousers with a wide or straight leg only need the thigh.
How do you measure your height?
Stand barefoot with your heels against a wall, look straight ahead, and have someone rest a book flat on your head against the wall; mark the wall under the book and measure from the floor. Height sets the proportions a pattern uses when it fills in lengths you have not measured, such as the knee position.
How much ease do trousers need?
Your measurements are the body; the pattern adds ease so you can sit and walk. A fitted woven trouser has about 2 to 3 cm (3/4 to 1 1/4 in) at the waist and 5 to 8 cm (2 to 3 1/8 in) at the hip; a wide-leg or pull-on trouser has 8 to 15 cm (3 1/8 to 6 in) at the hip, and a pull-on waist is cut to go over the hip and then drawn in with elastic. Do not add ease to your measurements yourself: give the body measurement and let the pattern add it. The ease chart by garment lists typical amounts.
What are the common measuring mistakes?
- Measuring over bulky clothes. Jeans add 2 to 3 cm around the hip. Measure in leggings or underwear.
- Breathing in at the waist and standing stiffly. Relax; you will wear the trousers while sitting at a desk.
- A tape that dips at the back on the hip measurement. Check in the mirror side on.
- Pulling the rise tight. The tape should touch the body without pressing into it.
- Different starting points for the rise and the outseam. The string prevents this.
- Rounding to the pattern's chart. Record your real numbers; the chart is for choosing a size, not for replacing your measurements.
If you give your measurements to a made-to-measure pattern, this is the set Sewly's measuring assistant asks for; it explains each one on screen and checks the numbers, but you still take them with a tape. Once the trousers are sewn as a toile, the wrinkles tell you what to refine.