Short answer: the Amazon suit size chart is not so much inaccurate as impossible. It asks one letter -- S, M, L, XL -- to describe a jacket, a waistcoat and a pair of trousers at once, on a body whose chest, waist, seat, arm length and torso length are all independent. It does not consistently run small or large. It runs different, in different directions, in the same parcel.
I am Jay. I spent about ten years in the US buying suits the normal American way; a year ago I came to Hoi An as a customer of Nathan Tailors and ended up a partner. Linda, born here and twenty-five years at the cutting table, leads the craft. I do the numbers -- so to test whether "a letter cannot describe a suit" is just tailor's snobbery, I read 399 reviews.
How did you get those numbers?
I pulled 399 customer reviews from the 8 best-selling men's suit listings returned for "mens suit", "mens slim fit suit", "mens wedding suit" and "mens 3 piece suit" -- priced $59.83 to $250 (median $67.92) as of September 2026, carrying 94 to 18,800 ratings each.5 Reviews dated January 2018 to September 2026.
The sample is deliberately not representative. Amazon serves reviews behind star filters and I took an even slice from each band: 112 five-star, 79 four-star, 66 three-star, 70 two-star, 72 one-star. So I never quote a percentage of all buyers. Every percentage here is a share of the 208 critical (1-3 star) reviews only.
A review counts as naming a fit failure if its text matches any of: "too small/big/large/tight/short/long/loose/baggy", "runs small/big/large/tight", "size up/down", "sizing", "size chart", "size guide", "wrong size", "doesn't fit", "poor fit", "ill-fitting", "snug". That is 69 of 208, or 33%.
Against my own argument: fit is not the top complaint. Buckets overlap, and material and quality vocabulary appears in 103 of 208 (50%), condition and packaging in 58 (28%). If you want a reason not to buy a $70 suit, the cloth is a better one than the fit.
Why does the jacket fit but the pants don't fit?
"I'm 6' and ~200lbs. I ordered the XL. The jacket fits great. It fits like my 44R's do. The pants aren't even close. I wear a 38 waist, and these can barely stretch to that... I also had to cut 3" off the ankle."2
Read what he told us without meaning to. His jacket is a 44. His trousers are a 38. That six-inch gap between chest size and waist size has a name in the trade: the drop. Every ready-made suit is cut to one assumed drop, and the seller picks it once, for everybody who buys that letter.
If your drop is bigger than the house drop -- broad chest, small waist, the gym build -- the jacket lands and the trousers swim. If it is smaller, the trousers land and the jacket strangles you. A reviewer at 5'9" and 205 lb got both from one XL: "The vest fit perfect, pants fit more like a 36 waist and would fall off. The jacket fit more like a 42r and would not button."6
Then there is rise -- crotch seam to waistband -- which no chart on those listings asks about, and which decides whether trousers sit on your hips or under your ribs. One reviewer matched the chart's stated 52-inch hip to his own and the trousers were still "extremely tight around the hips", while the waist, listed smaller at 43.3 inches, fit fine.7 That is not a chart wrong about a number. That is a chart with no number for the thing that failed. If you already own the suit and only one half works, our breakdown of what suit alterations really cost says which failures are fixable.
Why are the sleeves too short on a slim fit suit?
"Gonna keep this review short, but still not quite as short as the sleeves on this jacket which seemed to stop halfway between my wrists and my elbows. You may ask, 'But Matthew, did you not check the measurement chart?' To which I'll answer, 'why yes, I did.'"1
Because sleeve length is not a function of chest size, and ready-made sizing pretends it is. Thirteen of the 69 fit complaints name the sleeve, at every size: at 6'1" and 235 lb, "the XL jacket sleeves were too short and it was pretty tight across the shoulders"14; at 5'8" and 155 lb, "the jacket sleeves were too short so we had to send it back"19; at 6'5", a recommended 3X arrived with sleeves "just below the elbow, middle of forearm. Resembled an adult in a child's coat."15
And here is what matters about the word slim. Slim fit is a grading decision, not a length decision: sellers narrow the chest, waist and thigh, and usually shorten the body and sleeve too, because slim cuts are drafted on a younger, shorter reference body. So a tall, lean man -- exactly the man who thinks slim fit is for him -- gets the tightest chest and the shortest arms in one parcel. A commenter under Gentleman's Gazette's cheap-versus-bespoke video put the flip side plainly: "I have an easy to fit off the rack body which fits the standard cuts pretty much the way it is."22
One thing to know before you order: a sleeve that is too long is a cheap fix; a sleeve that is too short is not, because cheap jackets carry almost no spare cloth in the cuff. Which is why the reviewers who did best ordered up: "I ordered my size based on the shoulder and chest measurements (going the next size up) as the sleeve length, pants length, and waist can always be fixed with alterations. If a jacket fits too tight in the chest and shoulder, there's not much you can do."17 Best advice in the corpus, and it came from a four-star review.
Do Amazon suits use Asian sizing, and how do I convert it to a US size?
"Asian Suits, built for a EUR customer... I bought one of each size to account for it's Asian origin. Usually you have to size up. These suits are already sized for a EUR customer, and very strangely baggy and boxy. The shoulder pads are huge, and wide."3
And from a satisfied buyer: "I bought him an XL (tag says 4XL China sizing), and it fit beautifully."10 An American XL and a Chinese 4XL sharing one label is not a scandal -- it is a relabelling step -- but it tells you the letter is a marketing translation, not a measurement. For the real conversion, use the numbered systems, which do map cleanly:21
| System | ||||
|---|---|---|---|---|
| UK / US | 38 | 40 | 42 | 44 |
| EU / Russia | 48 | 50 | 52 | 54 |
| Japan | 40 | 42 | 44 | 46 |
| Korea | 100 | 105 | 110 | 115 |
Notice what is missing from every row: there is no S, M, L or XL anywhere in men's suit sizing. The letter is invented by the seller for the listing page -- no convention behind it, nothing to convert from. That is why "does Amazon run small" has no stable answer: you are asking the exchange rate on a currency each seller prints itself.
Practical rule: if a listing offers a numbered size (42R, 44L), take it and ignore the letters. If it offers only letters, ignore those too and buy from the centimetre or inch table underneath -- to your chest and shoulder, the two measurements alterations cannot rescue.
What size suit should a 6 foot, 200 lb man buy?
One of the highest-volume suit questions on the internet, and the honest answer is: there is no answer, and the reviews prove it. Every report in the corpus from a tall body near 200 lb:
| Reviewer's body | Size ordered | What actually happened |
|---|---|---|
| 6'0", ~200 lb | XL | "Jacket fits great... the pants aren't even close" -- 38 waist barely stretched, 3" cut off the ankle2 |
| 6'0", 190-200 lb | XL | "It fit beautifully." Pants a touch snug. Tag read 4XL China sizing10 |
| 6'0", 210 lb | XL, per the chart | Returned: "too baggy even though I followed the seller's sizing guide"13 |
| 6'1", 200 lb | XL | Vest fine; pants 2" too long; jacket wanted more room in midsection and shoulders12 |
| 6'0", 195 lb, athletic | - | Pants decent; "the jacket was way too short... extremely tight in the arms and chest"11 |
| 6'1", 220 lb, athletic | - | "Arms/back couldn't fit inside the jacket. Pants and vest fit fine though."16 |
| 6'1", 235 lb | L, XL and XXL together | XL pants right in the waist but baggy; XL jacket short in the sleeve, tight in the shoulder; XXL jacket fit. "We had to buy two just to get one suit that fit"14 |
| 6'2", 175 lb, lean | M -- chose it from reviews, not the chart | "The size medium set fit me perfectly in every aspect"20 |
| 6'4", 200 lb | XL | "It fits perfectly"23 |
| 6'4", 150 lb | M and L, both ordered | M coat near-perfect in the shoulders but 4" too big in the waist; pants short24 |
Four men within an inch and ten pounds of each other ordered the same XL and got four different suits, while a 6'2" 175 lb man and a 6'4" 200 lb man were both delighted -- in an M and an XL. Height and weight do not determine suit size. Chest, shoulder and arm length do, and two men of identical height and weight can differ four inches across the shoulders.
The strategy that worked most often above was buy two sizes, keep one, return one. Three reviewers did it deliberately14243 and it is the only reliable method in the corpus. Budget for the return trip, not for luck.
Is it fair to say the chart is just useless?
No, and I would be quoting selectively if I stopped here. Plenty of people follow the chart and are delighted. "Sizing chart is spot on... He is 5'6 and 150lbs with an athletic build."8 Another: "The sizing table said to order an XS... To my surprise, the pants and coat fit! The jacket fit well, the arm length was good, the shoulders didn't bind."9 A 5'7", 165 lb buyer took a small from the chart: "I didn't even have to have the pant length adjusted, which shocked me."25 A 6'0", 225 lb buyer took an XXL and reported "it fit perfectly."18
What they share is that they sit close to the reference body the pattern was drafted on. If you are roughly 5'6" to 5'10", average build, drop near six inches, ready-made sizing is a solved problem and you should not pay anybody -- us included -- to solve it again. The chart fails at the edges: tall, short, muscular, heavy, long-armed, short-waisted.
How do I measure once and stop guessing?
Every reviewer above was guessing with a tape measure they never picked up. Take the numbers once and you will read every size chart the way a cutter does -- comparing your number to their number.
- Chest -- decides whether a jacket is even possible.
- Shoulder width -- the one alterations genuinely cannot fix.
- Arm length -- the most-quoted failure in this article.
- Waist and rise -- whether the trousers work independently of the jacket.
- Jacket length -- why the same size reads as a crop top on one man.
Rather be walked through it? Our guided measurement studio does the whole set step by step with a 3D model showing where the tape goes, and our body-measurement percentile tool then places each number against real anthropometric survey data -- the fastest way to see why ready-made fails you. Chest at the 60th percentile and arm length at the 92nd? No letter on any listing was ever going to work, and now you know it instead of suspecting it. There is also a plain suit size calculator for a starting number.
So should I just buy a made-to-measure suit instead?
The honest trade-off, and it is not one-sided. Made-to-measure removes the chart problem completely, because there is no chart -- there is your chest, your shoulder, your arm, your rise, cut to those numbers. At Nathan Tailors that runs $149 to $309 for a suit, garment-only, as of September 2026, shipping quoted separately: two to four times a $67 Amazon suit, and typically 2-3 weeks door-to-door including express shipping, or two days if you are standing in our shop on Tran Hung Dao Street. If your event is Saturday, we are not your answer. Amazon is, and I mean that.
The maths turns when you count the second cheque. A commenter under The Dad Bod's "Best Suits UNDER $400": "I've tried the Mens Warehouse off the rack suits. The tailoring charges cost almost as much as the suit itself."26 A four-star Amazon reviewer said the same of her own purchase: "Alterations & dry cleaning for wrinkles were slightly more than the suit."17 On a published New York shop list, a sleeve shortening is $65, a trouser hem $30 and a waist take-in $35 -- $130 of work on a $67 suit, against a stated average of $165 for a full suit alteration.27 Add the return shipment for the size that failed and the $67 suit is a $200 suit with the wrong shoulders.
Two things I will not claim, because they are not true of us. We do not offer a remake guarantee and we do not reimburse alterations -- we cut with generous seam allowances and ship a piece of the same cloth, so a tailor near you can adjust it, and you pay that tailor. We also cut only from our own cloth library; we do not make up customer-supplied fabric. If those are dealbreakers, a brand with a formal fit guarantee is the better buy, and you can read what they actually promise on our Indochino alterations and Men's Wearhouse alterations fact pages.
The bottom line
The Amazon size chart is not lying to you. It is being asked to do what no chart can: describe a three-garment outfit with one letter, on a body it has never measured. Sometimes it lands. A third of the unhappy reviews are people it did not land on, and twelve of them did everything the listing asked.
If you are near the reference body and you need something by Friday, buy the $67 suit, order two sizes, keep the one that fits. If you keep losing this argument -- sleeves always short, trousers never matching the jacket -- the problem is not which size you pick. It is that you are picking a size at all. Measure once, then decide.
And if you do order from us: Linda will look at your photos, ask why you are so handsome, then quietly move the shoulder half an inch because she saw something you did not. That part does not come with a size chart. Start at custom tailored suits, ask anything at Hoi An questions, or see how ordering from abroad works on our online tailor page. Still deciding whether to own one at all? Rent or buy a suit for a wedding.
