How do you choose trouser length for your height?

Two women of the same height, the same trousers, two different results. On one the hem ends exactly at the ankle, on the other it gathers into folds over the shoe. Height does not decide trouser length, because the ratio of torso to legs varies even at an identical 170 centimetres.

Why is height not enough to choose the length?

Leg length is set by your inside leg measurement, not your overall height, because the same height can be divided differently between torso and legs. Between two women of the same height the difference can reach five centimetres.

Makers usually give one length per size, based on an average, so when you buy online the inside leg is a measurement you need to know, not guess. You take it from the crotch to the ankle with your leg straight, ideally without shoes. Keep the number on your phone together with your waist and hip measurements, taken as in the guide on how to measure your waist, because you will need it with every online order.

Where should a well-chosen hem end?

Where the hem ends depends on the cut, not on fashion: straight trousers end at the ankle, wide ones brush the top of the shoe, and tapered ones finish above the ankle.

The first two rows cover most trousers in a wardrobe. With a straight cut it is safer to take off an extra centimetre than to leave some spare, because excess fabric gathers into a telltale fold above the shoe.

A fabric with a little stretch behaves predictably here: in daylight the crease stays sharp even after hours of sitting, and in movement the leg falls back to vertical instead of bunching at the ankle.

How do height and shoes work together?

Length is set together with the shoes you will wear the trousers with most often, because a heel changes the effective length of the leg by its own height.

• If you are up to 160 cm. Shorten the hem so it shows the ankle. Every centimetre covered shortens the leg visually.
• If you are 160 to 175 cm. The standard length usually fits, simply check the cut against the table above.
• If you are over 175 cm. Look for a long version or a fabric with a deep hem allowance, because a standard length often ends above the ankle against the intention of the cut; see trousers for tall women.

Have trousers altered while wearing the shoes you will wear them with. The difference between flats and a seven centimetre heel is, in practice, a different length.

Which cuts can you safely shorten?

Shortening is the simplest fix, but not every cut can be shortened without upsetting its proportions. With flares and a wide leg, changing the length changes the width at the hem.

• Straight and tapered. Shorten freely, the cut will not suffer.
• Wide and flared. Take off three centimetres at most, beyond that the line of the leg changes. Before you decide, check how a wide leg is meant to fall.
• With turn-ups. Shortening means unpicking and refolding the turn-up, so it costs more.
• Joggers with cuffed hems. Practically impossible to shorten without losing the cuff, so choose the right size from the start.
• Linen. Shorten after the first wash, because linen can shrink by up to two centimetres. Allow for it when you buy.

What should you avoid when choosing the length?

Four habits lead to trousers that stay in the wardrobe unworn.

• Never measure the length without shoes if you wear heels. The difference reaches several centimetres and changes the whole effect.
• Avoid leaving extra length just in case. The fabric gathers on the shoe and wears through underneath.
• Never judge the length standing still in front of the mirror. Take a few steps, and you will see whether the leg rides up.
• Avoid shortening a wide leg by more than three centimetres. The hem becomes too narrow for the rest of the cut.

With a matching set, alter the trousers at the same time as the top, so the proportions of both pieces stay consistent, especially in sets cut from a single fabric. Remember too that natural fabrics shrink after the first wash. With pure cotton or trousers from the linen range, shorten after washing, not before.

How do you measure the inside leg?

Take a pair of trousers that fits you well, lay it flat and measure from the crotch seam to the end of the leg. That number is your reference point for every purchase that follows.

Do ankle-length trousers suit a petite figure?

Yes, it is an even more flattering length than full length, because a visible ankle lengthens the leg. Straight, high-waisted trousers work well here.

Which trouser length suits ankle boots?

The hem should end on the shaft of the boot or just above it, without a fold. With a tapered cut leave two to three centimetres of space, so no crease forms.

Is a long version worth buying?

It is if you are over 175 centimetres tall, because the standard length usually ends higher than the cut intends. With jeans the difference is often the greatest.

Go back to those two women of the same height. The whole difference lies in a single measurement that takes thirty seconds and, once taken, serves for years. The rest is matching it to the cut and the shoes.