How To · Fashion · Smart-Casual
The Complete Guide to Fit: Finding Your Size Across Brands
Fit is personal—and it varies wildly between brands. We'll show you how to decode your true size and shop with confidence, whether you're buying online or in-store.
5 min read · IrisYou know your shirt size. Or do you? A medium at one brand might swim on you at another—and that's not a reflection of your body. It's a reflection of how fragmented menswear sizing actually is. There's no universal standard, which means the same measurements can translate to wildly different fits depending on the brand's design philosophy, where it manufactures, and who it's designing for.
The good news: fit is learnable. With the right approach—knowing your actual measurements, understanding what different brands prioritize, and learning how to read a garment—you can navigate sizing variations like a pro and build a wardrobe that actually fits.
Fit is personal. The same size means nothing without context.
Step one · 2 minutes
Take your own measurements
Grab a soft measuring tape and wear a fitted t-shirt. Measure your chest (around the fullest part), shoulders (across the back from shoulder point to shoulder point), sleeve length (from the center back neck, across the shoulder, down to your wrist), and waist (at your natural waist, not your hips). Write these down—these are your anchor numbers. They don't change between brands; how brands interpret them does.
Have someone else help with shoulder measurement for accuracy. It's harder to get right alone.
Step two · 2 minutes
Study brand-specific size charts before buying
Every brand publishes a size chart—actually use it. Compare your measurements against the chart, not the size label. A brand that runs small will list a medium at 19.5 inches across the chest; another might list it at 21 inches. This is where the real information lives. If you're between sizes, check the brand's fit philosophy: does it prioritize a slim cut or a relaxed one? That tells you which direction to size.
Bookmark size charts for brands you shop regularly. Screenshot them on your phone for reference while shopping.
Step three · 2 minutes
Read customer fit reviews with intention
Online reviews aren't just about whether someone liked the shirt—they're a goldmine for fit intel. Look for comments like 'runs small,' 'generous in the shoulders,' or 'tapers at the waist.' Multiple reviewers saying the same thing? That's a pattern. Pay attention to whether reviewers mention their size and build. A 6'2" guy saying a medium is short is useful data if you're also tall.
Filter reviews by verified purchases and sort by 'most helpful.' Skip vague reviews and focus on specific fit observations.
Step four · 2 minutes
Understand the fit zones that matter most
Not all fit problems are equal. Shoulders should sit right at your shoulder point—this is non-negotiable and hard to alter. Chest room should let you move comfortably without pulling. Sleeve length should hit your wrist bone. Waist can be taken in or let out by a tailor. Prioritize getting shoulders and sleeve length right from the start; everything else is negotiable.
When trying on, raise your arms to 90 degrees. If the shirt pulls across the shoulders or back, it's too small. Move on.
Step five · 1 minute
Build a personal fit reference library
Find one well-fitting shirt, one pair of trousers, and one jacket in your closet that actually work. Measure them flat on a table (chest across the back, shoulder seam to seam, sleeve from shoulder seam to cuff, waist at the band). These become your benchmarks. When shopping new brands, compare their measurements to your reference pieces. If your favorite shirt measures 20 inches across the chest and a new brand's medium measures 21.5, you know to size down.
Take photos of your measurements and store them in your phone. Include the brand name and size so you can spot patterns over time.
Step six · 1 minute
Know when to order multiple sizes
Online shopping means you can hedge your bets. If a brand's chart suggests you're between a small and medium, order both. The return process exists for exactly this reason. Try them on at home under good light, move around, and keep the one that fits. This removes the guesswork and gives you real data about how that brand actually fits your body.
Check return policies before ordering. Free returns make this strategy viable; paid returns don't.
How to know fit is working.
Good fit feels invisible. You shouldn't think about your clothes while wearing them. The garment moves with your body, not against it. Seams sit where they should. You can raise your arms, sit down, and move freely without pulling or bunching. If you're constantly adjusting or aware of tightness, the fit isn't right.
Questions at the mirror.
I'm between sizes on the chart. Which do I choose?
Look at what you're buying. For structured pieces like blazers, size up slightly for comfort. For fitted basics, size down if the brand runs generous. When in doubt, order both if possible. Your reference garments will tell you which direction to go.
A brand's size chart doesn't match what reviewers say. Who's right?
The reviewers, usually. Brands occasionally update their manufacturing without updating charts. If multiple customers report the same fit issue, trust the pattern over the official numbers.
How much should a tailor cost for basic alterations?
Hemming sleeves or tapering a waist typically runs $15–40 depending on your location. It's worth doing for pieces you love, but don't plan on major alterations. Good fit should start with the right size.
Does fit change between fabric types at the same brand?
Sometimes. A cotton oxford shirt might fit differently than a linen one from the same brand due to how the fabric drapes. Check reviews for the specific fabric, not just the style.