How to measure your waist (and why pants differ)

Your waist measurement is the distance around your natural waist: the narrowest part of your torso, usually a little above the belly button. Dresses, tops and most body measurement charts use that line. Pants and jeans often sit lower, which is why your pant size and your waist measurement may not match.

How to measure your natural waist

1. Find the line. Stand straight and bend to one side: the crease that forms is your natural waist. At the front, it is usually above the belly button.
2. Bare skin or a thin layer. No belt, no jeans waistband under the tape.
3. Relax. Weight on both feet, and don't pull your stomach in.
4. Wrap the tape level. Around the narrowest part, flat against the skin, horizontal all the way round. A mirror helps you check the back.
5. Breathe out normally and read. Snug, not pressing in. Write down the unit with the number.

How to measure where your pants sit

1. Put on pants that fit and note where the top of the waistband rests: at the natural waist, below the belly button, or lower on the hips.
2. Measure your body on that line, the tape level, as above. Keep both numbers: most charts don't say which waist they mean, and this one is closer to what your pants close around.
3. Or measure the pants. Lay them flat and buttoned, and measure straight across the top of the waistband. Double it: that is the garment's waist, usually a little larger than the body it fits.

Why pant sizes differ from your waist

Pant sizes are names for ranges. In the Men's pants template of Ruban Size, a size 32 fits a body waist of 32 to 33 in, and every size works the same way:

Another brand can cut its 32 for a different waist, and the rise moves the waistband up or down your body, where you may be wider or narrower than at the natural waist. Labels can also drift smaller than the bodies they fit (see what vanity sizing is). So measure, then read the brand's chart, not the number on your old pair.

Jeans follow the same logic. The Women's jeans template runs from 24 to 34: a 24 fits a waist of 24 to 25 in and hips of 33 to 34 in, a 34 a waist of 34 to 35 in and hips of 43 to 44 in. Its fit note reads "Stretch-free denim: if you are between two sizes, take the larger one." Rigid denim doesn't give, so the waist and the hips both have to fit, and the hips guide covers the other half.

Common mistakes

• Pulling the stomach in. You won't hold it all day in the pants.
• Measuring over a waistband or a belt.
• A tape that tilts, lower at the back than at the front.
• Taking your pant label as your waist. The label is the brand's name for a range.
• Mixing the two lines. Natural waist for dresses and tops; the waistband line for pants that sit low.
• Typing centimeters into an inch chart. 81 is a size 32 waist in centimeters, and far above the largest size in inches.

What it means for a Shopify store

A waist row only helps if shoppers know which waist it is. Say "body measurements" or "garment measurements" above the table, and if your pants sit low, add one line on where to measure. The Men's pants template opens with exactly that: "Measurements are body measurements, in inches."

Keep both units. Pant sizes like 32 are inches, while many shoppers outside the US measure in centimeters. In a Ruban Size size chart, every row converts with the cm/in switch, and shoppers in the US see inches first by default.

How Ruban Size handles the waist

Most clothing templates have a waist row, with the step "around your natural waistline, the narrowest part of your torso." The Men's pants template is in inches, sizes 28 to 40, and the Women's jeans template runs from 24 to 34. The pants template has no measuring block of its own, so the guide adds a collapsed How to measure section built from its table: waist, hips and inseam, beside the body figure. Point at or tap the waist step and the waist line lights up in the figure and in the table.

Find my size asks for the measurements the chart has, in the units shown, and catches the classic mix-up: "These look like centimeters, and the fields are in inches.", with a button to switch. A 33 in waist on the Men's pants template, which is set to "Runs slightly small", reads:

• "You are between 32 and 34. We suggest 32."
• "Waist 33 in: 32, between 32 and 34"
• "34 may also fit if you like more room."
• "This item runs small: we took it into account."

Waist and hips both count on pants, and the one that needs the larger size wins: a 32 in waist with 42 in hips gets 36 on the same chart, because pants that close at the waist but not over the hips can't be worn.

When a chart lists the garment's own waist, laid flat or around, Find my size adds room before comparing: 2.5, 3.2 or 3.8 cm at the waist of pants for Snug, Regular and Loose, and 1.3, 2.5 or 3.2 cm for jeans, from the ease table of its engine. In the Fit tab of the chart you can also mark the fabric as stretch, set the main measurement, and check the size a shopper would get with "Try it".

Questions

Is my waist size the same as my pant size?

Not always. In the Men's pants template, a size 32 fits a 32 to 33 in body waist, but another brand's 32 may be cut differently or sit lower. Measure, then read that brand's chart.

Where is my natural waist?

The narrowest part of your torso, usually a little above the belly button. Bend to one side: the crease that forms is your natural waist.

How do I measure the waist of a pair of pants?

Lay them flat and buttoned, measure straight across the top of the waistband, and double it. That is the garment's waist, usually a little larger than the body it fits unless the fabric stretches.

How do I convert my waist from centimeters to inches?

Divide by 2.54. An 81 cm waist is 31.9 in, and a 32 in waist is 81.3 cm.