Sizing, measured
83 guides to measuring, converting sizes and running size charts on Shopify. The numbers come from the templates and the formulas inside Ruban Size, and many guides carry the real size guide, working.
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- Shopify guidesHow to add a size chart to ShopifyFour ways to add a size chart to a Shopify store, where each one falls short on phones and per product, and the steps with a size chart app.6 min read
- Size conversionRing size conversion chart: US, UK, EU and JapanUS, UK, EU and Japanese ring sizes by inner circumference and diameter, from US 3 to 13, with how each system is defined and where it comes from.6 min read
- Sizing explainedHow much ease clothes need: the numbers by garmentEase is the room between body and garment. The numbers by garment in cm and inches, from the Vogue, Butterick and McCall's ease allowances and more.7 min read
How to measure
Step by step, for shoppers and for the stores that publish the charts: chest, waist, inseam, feet, rings, bras, heads, hands, dogs and kids.
- How to measure your chest for clothesPass the tape under your arms and around the fullest part of your chest, keep it level all the way round, and read it after a normal breath out. That number is your chest; on a women's chart labeled bust, the tape takes the same path.6 min
- How to measure your waist (and why pants differ)Measure your natural waist around the narrowest part of your torso, tape level, after a normal breath out. For pants and jeans, also measure where the waistband actually sits, because a pant size like 32 is a label, not always your natural waist.5 min
- How to measure your hipsStand with your feet together and wrap the tape around the fullest part of your hips and seat, level all the way round. That is the hip measurement dresses, swimwear, leggings and jeans are sized by, and often the one that decides.5 min
- How to measure inseam, and how it differs from outseamInseam is the length from the crotch to the floor along the inside of your leg, measured without shoes; on a pair of pants, from the crotch seam to the hem. Outseam runs down the outside of the leg from the top of the waistband, and shoppers' size charts rarely use it.5 min
- How to measure shoulder width and sleeve lengthShoulder width runs across the top of your back, from the bony tip of one shoulder to the other. Sleeve length runs from that shoulder point, over a slightly bent elbow, to the wrist bone; dress shirts measure it from the center back of the neck instead, so check which one a chart means.5 min
- How to measure your neck for a dress shirtWrap the tape around the base of your neck, where a shirt collar sits, with one finger slipped under it, and read the number. That is the neck size a dress shirt chart asks for: on the Men's shirts template, 39 to 40 cm is an M and 41 to 42 cm an L.5 min
- How to measure your foot length and widthStand on a sheet of paper with your heel against a wall, mark the tip of your longest toe, and measure from the wall to the mark: that is your foot length. For width, measure straight across the widest part of the foot. Do both feet and keep the larger numbers.5 min
- How to measure your ring size at homeWrap a strip of paper around the base of your finger, mark where it overlaps and measure the length in millimeters: that is your inner circumference, and your EU ring size. No paper? Measure across the inside of a ring that fits the same finger: that is the inner diameter.5 min
- How to measure your bra sizeYour band is your underbust rounded to the nearest 5 cm. Your cup comes from your bust minus your underbust: AA from 10 cm, then one letter for every 2 cm.7 min
- How to measure your head for a hat or a helmetMeasure around your head just above the eyebrows and ears, where a hat sits, and keep the largest reading. Between two sizes, take the larger one, for hats and helmets alike.6 min
- How to measure your hand for glovesGlove sizes follow your hand circumference, measured around the knuckles with the thumb left out. Hand length, from the wrist crease to the tip of the middle finger, settles the close calls.5 min
- How to measure your wrist for a bracelet or watch strapWrap a strip of paper just below your wrist bone, mark the overlap and measure it. Add 1.3 cm for a snug bracelet, 1.9 cm for a comfortable one and 2.5 cm for a loose one.5 min
- How to measure a dog for a coat or sweaterThree measurements, with your dog standing: the neck where the collar sits, the chest at its widest just behind the front legs, and the back from the base of the neck to the base of the tail. Choose by chest first.5 min
- How to measure kids for clothes: age, height or bothChoose kids' clothes by height first, then check the chest or the waist. The age on the label is only a guide: a tall four-year-old can wear a 5Y.5 min
- How to measure a garment flat for your size chartLay the garment flat and measure straight across from armpit to armpit, from the top of the shoulder to the hem, and along the sleeve. Then write "laid flat" in the header, so nobody takes half a chest for a whole one.6 min
- How to measure your belt sizeLay a belt that fits you flat and measure from where the strap meets the buckle to the hole you use most: that length is your belt size. No belt to measure? Take your trouser waist size and add 2 in (5 cm), so a 32 trouser takes a 34 belt.5 min
- How to measure biceps and thighsFor clothes, measure your biceps with the arm relaxed at your side, around the fullest part of the upper arm, and your thigh standing, around the fullest part of the leg just below the crotch, tape level. On a garment laid flat, measure straight across the sleeve or the leg at the same points and double it.5 min
- How to measure torso length for swimsuits and bodysuitsTorso length for a one-piece swimsuit or a bodysuit is a loop. Start on top of one shoulder, run the tape down over the bust, between the legs and up the back to the same shoulder, standing straight with the tape snug.5 min
- How to measure for a suit jacketMeasure your chest over a thin shirt, under the arms and around the fullest part, tape level: that number picks the jacket size. Then measure shoulders, sleeve and back length, which tell you whether you need a short, regular or long.6 min
- How to measure a dress for your size chartLay the dress flat and closed, then measure straight across the bust (armpit to armpit), the waist and the hips, and from the top of the shoulder down to the hem. The widths are halves: double them for the measurements around, and say in the chart which ones you publish.6 min
- How to measure pants and jeans flat: rise, thigh, leg openingButton the pants, lay them flat front up, and measure straight across the waistband, the hips, the thigh, the knee and the leg opening; then the front and back rise from the crotch seam to the top of the waistband, and the inseam down to the hem. The widths are halves, so double them for the measurements around.7 min
- How to measure a skirt: waist, hips and lengthMeasure your waist where the skirt's waistband will sit, your hips around the fullest part with your feet together, and the length from that waist line down to where you want the hem. On a skirt laid flat, measure across the waistband and the hips, double both, and measure the length from the top of the waistband to the hem.5 min
- How to measure a baby for clothesLay the baby on their back, legs gently straightened, and measure from the top of the head to the heel. That length, with the weight, picks the size; the months on the label (0-3 M, 3-6 M) are only a guide.5 min
Size conversion
US, UK, EU and Japanese sizes for rings, shoes, bras and clothes, computed with the same formulas as Find my size.
- Ring size conversion chart: US, UK, EU and JapanA US 7 ring measures about 54.4 mm around the inside and 17.3 mm across. That is UK N 1/2, EU 54.5 and Japan 14. The full chart, from US 3 to 13, is below.6 min
- Shoe size conversion chart from foot lengthA 26.5 cm foot (10.4 in) is about EU 42, UK 8.5, US men's 9.5, US women's 10.5 and JP 26.5. The chart below runs from 22 to 30 cm; a brand's own chart always wins.6 min
- Kids' shoe size chart by foot lengthA child's foot of 16 cm (6.3 in) is about EU 26, UK 9, US 9 and JP 16 on the children's scales. The chart covers 10 to 19.5 cm; past that, UK and US sizes start again at 1.6 min
- Bra size conversion chart across 7 systemsA European 75C is 90C in France, 3C in Italy, 34C in the UK and the US, 12C in Australia and C75 in Japan. Bands convert by fixed rules; cup letters match up to D, then the UK and US letters part ways.6 min
- Women's clothing sizes: US, UK and EU comparedA women's M is US 8 to 10, UK 12 to 14 and EU 40 to 42, for a bust of 90 to 95 cm (35.4 to 37.4 in). In these charts, UK numbers run 4 above US ones and EU numbers 32 above.6 min
- Men's clothing sizes: suits, shirts and pants comparedA men's EU 50 suit is a UK and US 40, for a chest of 98 to 101 cm. In suits, the EU number is the UK/US number plus 10; shirts go by neck size, and pants by waist and inseam in inches.6 min
- Kids' clothing sizes by age and height (2T to 14)Kids' sizes follow height more than age. A 4T fits about 100 to 106 cm, a size 8 about 125 to 130 cm and a 14 about 151 to 160 cm. The tables below come from Ruban Size's kids' templates.5 min
- Hat sizes: head circumference to US hat sizeA US hat size is your head circumference in inches divided by pi. A 57 cm (22.4 in) head is a 7 1/8, size M in Ruban Size's Hats template. The chart covers 54 to 61 cm, with kids' hats and helmets after it.5 min
- Centimeters to inches for size charts, fractions includedAn inch is exactly 2.54 cm, so divide centimeters by 2.54. Round body measurements to the quarter inch, small ones like hands and feet to the eighth, and heights to the whole inch in feet and inches.5 min
- Sock sizes: shoe size to S, M, LA sock size M fits US shoe sizes 7 to 9 and EU 39 to 42, a foot of about 24.7 to 26.7 cm. Each sock size covers three US shoe sizes and four EU sizes, from S (US 4 to 6) to XL (US 13 to 15).5 min
- Necklace length chart: collar to ropeA princess necklace is 45 cm (18 in) and sits on the collarbone. A choker is 40 cm (16 in), an opera 60 cm (24 in) and a rope 90 cm (36 in). The full chart, from collar to rope, is below.5 min
- Baby clothing sizes by age, height and weightBaby sizes are labeled by age, but height decides. A 0-3 M fits about 50 to 62 cm, a 3-6 M 62 to 68 cm and a 6-12 M 68 to 80 cm, with weight as the second check. The full chart, to 24 months, is below.5 min
- What number is a small, medium or large?In Ruban Size's women's dress and top templates, a small is a US 4 to 6, a medium a US 8 to 10 and a large a US 12 to 14 (UK 8 to 10, 12 to 14 and 16 to 18; EU 36 to 38, 40 to 42 and 44 to 46). Men's letters have no number of their own: they go by chest.6 min
- Japanese, Chinese and Korean clothing sizes explainedA Chinese label like 170/88A means 170 cm tall, a chest of 88 cm and body type A. A Japanese women's size like 9AR codes the bust, the hip type and the height. Korean tags give the chest or the height in centimeters. Read those numbers, not the letter.6 min
- Shoe widths explained: B, D, E, EE and wide fitIn US sizes, D is the standard shoe width for men and B the standard for women. Each letter is one step of 3/16 in (4.8 mm) on the Brannock scale: E, EE (2E) and beyond are wider, the letters before the standard narrower. A width only means something next to a length.5 min
- Swimsuit sizes: bust, underbust, waist and hipsA swimsuit M fits a bust of 88 to 93 cm, an underbust of 76 to 80, a waist of 70 to 75 and hips of 96 to 101 cm: a US 8 to 10, EU 40 to 42. Swim fabrics fit close, so between two sizes, take the larger one.5 min
- Scrubs sizes: tops, pants, regular and tallA scrubs M fits a chest of 95 to 102 cm, a waist of 78 to 85 and hips of 100 to 107 cm. Tops go by the chest, pants by the hips, and tall pants add 8 cm (about 3 in) of inseam: 86 cm against 78 for an M.5 min
- Helmet sizes by head circumferenceHelmets are sized by head circumference. In Ruban Size's Helmets template, S is 55 to 56 cm, M 57 to 58 cm and L 59 to 60 cm (M is 22.4 to 22.8 in). Measure around the widest part of the head, and between two sizes take the larger one.5 min
Sizing explained
What the words on a size chart mean: true to size, ease, garment measurements, petite, plus, sister sizes.
- What "true to size" means, and how to show itTrue to size means an item fits the way its size chart says, so shoppers take the size the chart gives them. A store shows it best on a fixed scale from runs small to runs large, with one line of fit note.6 min
- What vanity sizing is, and what a store can do about itVanity sizing is labeling clothes with a smaller size than their measurements would earn, so the number flatters. A store can't fix labels across an industry, but it can publish the measurements behind its own.5 min
- Body measurements vs garment measurementsA body measurement is the person; a garment measurement is the product, often laid flat and halved. The gap between the two is ease, and comparing one with the other is the quickest way to a wrong size.6 min
- How much ease clothes need: the numbers by garmentEase is the garment measurement minus the body measurement. A fitted top needs about 8.9 cm (3.5 in) at the chest, a regular one 11.6 cm (4.6 in), a regular coat 18.9 cm (7.4 in). The full table by garment is below.7 min
- Petite, tall, plus size, big and tall: what each meansPetite and tall are about length: the same widths, cut shorter or longer. Plus size and big are about girth: a larger chest, waist and hips. Big and tall is both at once.6 min
- Bra sister sizes explainedSister sizes hold the same cup volume on a different band. Go one band down and one cup up, or one band up and one cup down: the sisters of a 34C are 32D and 36B.5 min
- Size chart vs size guide: what's the differenceA size chart is the table: sizes on one side, measurements on the other. A size guide is everything a shopper needs to use it: the chart, how to measure, how the item fits, and a way to get a size from their own numbers.5 min
- Why a medium isn't the same size at every brandA medium is a name, not a measurement. Each brand decides which body its M fits, how much room it leaves and how sizes step up, so the fix is to publish the measurements behind your M and a one-line fit note.5 min
- Junior, youth and women's sizes: what's the differenceYouth sizes are children's sizes, chosen by height and age. Junior sizes, in odd numbers like 3, 5 and 7, are cut for teens and young women with a straighter shape. Women's sizes, in even numbers like 4, 6 and 8, are cut for an adult figure.6 min
- What "one size" means, and when it fitsOne size means the maker cut a single size to cover a range of bodies, through stretch, an adjustment or a loose cut. It fits when your body falls inside that range, so a one-size product should still say, in numbers, which bodies it fits.5 min
- How size grading works: from one sample to a size rangeGrading turns one approved sample into a full range of sizes. Every point of the pattern moves by a set amount per size, the grade rule. Girths grow by several centimeters a size, lengths by one or two, and the steps often widen toward the larger sizes.6 min
- Tolerance: why a garment can measure 1 cm off the chartTolerance is how far a finished garment may measure from its spec and still pass. Fabric, cutting, sewing and the tape itself all move the numbers a little, so a chart value is a target, not a promise to the millimeter. Keep the tolerance under half the step between sizes.6 min
- Maternity sizes: why you keep your usual sizeMaternity clothes use your pre-pregnancy size: if you wore a medium before, you take a maternity medium. The room for the bump is built into the cut and the fabric. Bras are the exception: measure again, because band and cup both change.5 min
- Activewear and compression sizing: tight on purposeActivewear and compression garments are made smaller than the body, so they hold. Size them by the brand's chart, not your usual letter, and follow the fit note: Ruban Size's templates say size up for comfort on leggings and cycling kit, size down for support on sports bras.6 min
Shopify guides
Adding size charts to a Shopify store: placement, rules per product, themes, metafields, languages, phones and speed.
- How to add a size chart to ShopifyShopify has no size chart tool of its own, so you add one with an image, a page, metafields or an app. An app gives you real tables, the right chart on each product and a cm/in switch; the other ways mostly get you an image.6 min
- How to show a different size chart on each Shopify productLet the data your products already carry pick the chart. A rule on a tag, a product type, a vendor or a collection covers most catalogs, title and SKU conditions catch the rest, and exclusions and priority settle the overlaps.6 min
- Where to put the size chart on a product pageRight next to the size option, above Add to cart, as a link that opens the chart without leaving the page. On phones, a panel that slides up from the bottom. Inline and accordion layouts suit pages where the chart belongs in the details.5 min
- Adding a size chart to the Dawn and Horizon themesTurn on the app embed in the theme editor and save: on Dawn and Horizon, the Ruban Size link lands next to the size option by itself. Add the app block instead when you want a fixed spot, or the chart inline on the page.5 min
- Size charts and Shopify metafields: how they fit togetherMetafields add your own fields to products, and metaobjects let you define a kind of content, like a size chart, once and reuse it. You can build a chart from them yourself. Ruban Size uses the same pieces, so your charts live in your store and show without its servers.5 min
- How to translate size charts on ShopifyTranslate the words of a chart (its title, headers, measuring steps and notes) and leave sizes, numbers and size systems as they are. With Ruban Size, the guide's buttons already speak 22 languages and charts are translated in the app, field by field, with no Translate & Adapt needed.5 min
- Size charts on phones: why image charts failAn image chart made on a desktop shrinks to the width of a phone, so its numbers get too small to read, and it can't switch units, be searched or be read aloud. A real table in a panel that slides up from the bottom, with headers that stay put and big tap targets, fixes all of it.5 min
- Will a size chart app slow down your Shopify store?It can, but it doesn't have to. A size chart slows a page when the app fetches it from its own servers on every visit or loads heavy scripts up front. Written into the page by your theme from your store's own data, with a small script to open it, it costs very little.6 min
- How to make a size chart for your brand, from your samplesMeasure one finished piece of every size at the same points, laid flat, and write the numbers in a table with the sizes across the top. Check that each size steps up evenly from the last, say whether the numbers are the garment's or the body's, and add how to measure and a fit note.6 min
- How to add sizes to Shopify products as variantsOpen the product in your Shopify admin, add an option named Size in the Variants section, and type one value per size. Shopify makes a variant for each, with its own price, SKU and stock, and your theme shows them as the size picker.5 min
- Size info in product page tabs and accordionsTabs and accordions are a good home for the full size chart, how to measure and fit notes, as long as a size guide link also sits next to the size option. A tab below the buy button is easy to miss on a phone; the link is where the size gets chosen.5 min
- A free size chart for Shopify: what you can do at $0At $0 you can paste a chart into a product description or a page, build one from metafields, or use a free app plan. Ruban Size's Free plan holds 5 active size charts with every rule, the 39 templates and Find my size, in a popup with a small credit line.5 min
- A size guide page for your whole Shopify storeA size guide page lists every size chart of your store on one page, for shoppers who check sizes before they browse. Create a page in Shopify, give it a template with a size guide block, and link it from your menu. It adds to the link on each product; it doesn't replace it.5 min
Returns
Fewer parcels coming back for the wrong size: what to publish, what to read in your returns, what to change.
- How to reduce size returns in a Shopify storeA size return is a shopper who guessed. Put a readable chart next to the size option, in their units, with how to measure and a fit note, give them a size from their own measurements, then read which sizes still come back.6 min
- Why shoppers order two sizes, and how to stop itShoppers order two sizes when they can't trust any single one. Give them one size with its reasons, keep it for them on every product, and show a neighbor size only when it is a real alternative.5 min
- Reading your returns by sizeCount each size's returns as too small against too big. When one size keeps coming back the same way, the chart or the cut is off for that size, so fix the numbers or the fit scale. Ruban Size does the counting from Shopify's return reasons.6 min
- Fit notes that help: "runs small" and the fit scaleA fit note helps when it names the cut and says what to do: "Slim cut: if you are between sizes, take the next size up." Put it under a fixed five-step fit scale, and let the size finder move its answer with the scale.6 min
- Writing a size exchange policy shoppers trustA size exchange policy shoppers trust answers five questions with numbers: how long they have, what state the item must be in, who pays the shipping, what happens if the new size is sold out, and how to start. Put one line of it in the size guide and the same numbers on your policy page.6 min
- Return reasons that tell you what to fixA return reason helps when it says which way the size missed (too small or too big) and, better still, where (the waist, the sleeves, the band). "Doesn't fit" points nowhere, and "changed my mind" isn't about the chart. Ask for a reason on every return, then read them by size.6 min
Size chart apps
The Shopify size chart apps side by side, with their prices as published.
- The best Shopify size chart apps in 2026, comparedThe right size chart app comes down to three numbers: how many charts you need, how many orders you take, and whether you want a size recommender. Unlimited charts are listed from $4.99 a month; recommenders and usage fees are where the plans differ most.5 min
- Kiwi Size Chart alternatives in 2026Stores look for a Kiwi Size Chart alternative when the usage fee grows with their orders, or when they need more languages than their plan translates. ESC, CSC, Jotly and Ruban Size list unlimited charts at $4.99 to $6.99 a month, and Ruban Size imports your Kiwi charts with the products they show on.5 min
- ESC Size Charts alternatives in 2026ESC Size Charts lists unlimited charts at $4.99 a month and no size recommender. Ruban Size lists unlimited charts at the same $4.99 with Find my size on every plan, and CSC and Jotly list unlimited charts at $6.99. Ruban Size finds your ESC charts on your store and recreates them with their products.6 min
- MP Size Chart alternatives in 2026Two lines of MP Size Chart's pricing page send stores looking: unlimited charts are on Pro, at $12.95 a month, and there is no export. Ruban Size lists unlimited charts at $4.99 with an export on every plan, and reads your MP charts from your store, so nothing needs exporting.6 min
- BF Size Chart alternatives in 2026BF Size Chart lists the lowest first price, $2.99 a month for 10 charts, and a free plan with no watermark. Past 10 charts its unlimited plan is $11.99, and it lists no size recommender. Ruban Size lists unlimited charts at $4.99 with Find my size on every plan, and imports your BF charts from your store or BF's export file.6 min
Find my size
Size recommenders: how they work, what they can and cannot know, and how Find my size reaches its answer.
- What a size recommender is, and the three kindsA size recommender turns what a shopper knows about their body into one size of your chart. It works from their measurements, from an estimate based on height, weight and age, or from a quiz or a model trained on past orders. Each kind trades the shopper's effort against certainty.5 min
- How Find my size works, step by stepFind my size reads your chart as ranges with no gaps, works out a target for each measurement, scores every size, and shows the best one with how sure it is and why. It runs on the shopper's device and never suggests a size beyond your largest.7 min
- Can you guess a size from height and weight?Roughly, yes. Equations from large body surveys estimate chest, hips and waist from height, weight and age, but two people of the same build can differ by about a clothing size. Show the result as an estimate with the chances of each size, and invite the shopper to measure.6 min
- Size quiz or measurements: which finds the right size?Measurements find the right size more often, when the shopper has a tape and the chart has measurements. A quiz is faster and works without either, at the cost of an estimate. Offer measurements first, and an estimate from height and weight for shoppers who can't measure.5 min
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