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The Complete Clothing Size Guide for Brands
Size charts, grading logic, and fit tools — everything you need to build a size system that works across markets and minimizes returns.
Browse All Sizing ToolsFree Interactive Tools
Size charts are one of the most underestimated decisions in clothing brand development. Get them wrong at the product design stage and you are not just generating returns — you are generating fit complaints that follow your brand across reviews and stockists.
This guide is built for clothing brands and brand founders, not for consumers looking up their own measurements. The focus is on decisions that happen before production: how grading works, how to set up a size range that fits your target market, how to decide which sizes to stock and in what ratio, and which tools make the process accurate rather than approximate.
Why sizing is more complex for brands than it looks
Consumer-facing size guides reduce sizing to a conversion table. That is useful for buyers, but it hides most of the real complexity. For a clothing brand, the important questions are: how many sizes do you grade your block into, what are the increment measurements between each size, how does oversized grading differ from regular-fit grading, and how do you build a size run that balances coverage against inventory risk?
The answers vary by garment category, by target market, and by the fit standard you are designing toward. A streetwear hoodie with an oversized block grades differently from a dress shirt. Children's sizing follows different logic from adult sizing. Accessories like hats and gloves have their own sizing conventions that are frequently misunderstood even by experienced brand teams.
How to use this guide
Section 01 covers sizing strategy and grading fundamentals — start here if you are setting up a size system for the first time or auditing an existing one. Section 02 covers size charts by garment category with technical details for each. Section 03 covers accessories, which are commonly handled as a separate sizing system. The free tools in the strip above are designed to make the technical work faster.
01 — Understanding Size Systems & Grading
Before you finalize your size chart, you need to understand how grading works — and why the "standard sizes" you find online are rarely standard at all.
The Size Chart Struggle Is Real: Why It's So Hard to Get Right
Why sizing is one of the most underestimated decisions a new brand makes — and how to fix it.
Size Chart GuideSize Chart Guide for Fashion Brands: Principles & Grading Logic
The principles behind building a size chart that actually fits your customer — and scales with your line.
Size RunWhat Is a Size Run? A Strategic Guide to Sizing Ratios
How to decide which sizes to order and in what ratio — one of the most important inventory decisions you'll make.
02 — Size Charts by Category
Every garment category has its own sizing conventions. These guides cover the technical details — measurements, grading increments, and fit standards for each.
Children's Clothing Size Chart Guide
Age vs. height vs. weight — how kids' sizing actually works and how to set up a range that covers your market.
TopsHoodie Size Chart Guide: Oversized, Regular & Streetwear Fits
Streetwear sizing is not standard sizing. Here's how oversized grading works — and how to spec it for production.
ShirtsDress Shirt Size Chart: Barcodes, Grading & Technical Guide
The technical side of dress shirt sizing — neck, sleeve, chest grading and how barcodes tie into your SKU system.
TailoringSuit Jacket Size Chart: A Technical Guide
Drop ratios, chest vs. waist grading, and the fitting conventions that differ between markets.
03 — Accessories & Headwear Sizing
Accessories often get treated as afterthoughts — but sizing errors in hats and gloves generate some of the highest return rates in accessories categories.
Hat & Cap Size Chart Converter
Convert between US, UK, EU, and cm sizing in real time. Used by brand founders and buyers.
Free Tool AccessoriesGlove Size Chart
Hand measurement guide with size conversion across markets. Includes fit tips for different glove constructions.
HeadwearThe Science of Hat Sizing
Why hat sizing is more technical than it looks — oval heads, stretch factors, and how to spec your headwear range.
AccessoriesWhat Glove Size Am I?
A buyer-friendly guide to measuring hand size and choosing the right glove fit — useful for your own size guide pages.
Frequently Asked Questions
What is grading in clothing manufacturing?
Grading is the process of scaling a base pattern up or down across a size range. Each size step involves specific increment changes to measurements like chest, waist, hip, and sleeve length. Grading rules vary by garment category, fit type, and target market. A dress shirt grades differently from a streetwear hoodie — the increments, proportions, and key measurement points all change depending on the construction and the customer body you are designing for.
How do I create a size chart for my clothing brand?
Start with a fit block — a base garment pattern built to your target customer's body measurements. Grade that block into your full size range using consistent increments. Then build a finished garment measurement (FGM) chart, which specifies the actual dimensions of the garment at each size — not the body measurements. Factories use FGM charts for production, not body measurement ranges. The Size Table Builder on this page can help you structure and export yours.
What is a size run, and how do I decide which ratio to order?
A size run is the distribution of sizes within a production order — for example, 100 pieces split as XS×5, S×20, M×35, L×25, XL×15. The right ratio depends on your target market and, if available, historical sales data. For a first run with no data, a common starting point is to weight toward M and L, which cover the largest range of customers in most North American markets. The Size Run Planner gives recommended ratios based on category and market.
How do I reduce return rates caused by fit issues?
Most fit-related returns come from inaccurate size charts, not from customers measuring themselves incorrectly. The fix is to publish finished garment measurements — the actual dimensions of the garment laid flat — rather than generic body measurement ranges. Include at minimum chest, length, and shoulder width for tops; waist, hip, and inseam for bottoms. Adding a clear fit note (e.g. "this style runs oversized — size down for a regular fit") further reduces returns by setting expectations before purchase.
Need Help Building Your Size System?
We help clothing brands set up grading structures that work for their target market — before sampling, so you don't waste rounds fixing fit.
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