You have likely spotted a pair of boots or sneakers online that look perfect and cost half of what you’d pay at a boutique. Then you hit the size dropdown, and it's a list of cryptic numbers. This is where a reliable Chinese shoe size guide becomes your best friend.
As we settle into 2026, ordering direct from Asian markets has moved from a niche habit to a standard way we stock our wardrobes. But the return process for international shipping has only gotten stricter since the logistical shifts of 2025. You cannot afford to guess anymore. A "size 8" is not universal, and treating it like one is the fastest way to end up with blisters or a closet full of unwearable shoes. Let’s strip away the confusion and look at the actual mechanics of how CN sizing works compared to the US standard.
Key Takeaways: The Cheat Sheet
If you are in a rush to checkout, here is the harsh reality of international sizing.
-
CN sizes are based on millimeters. A size often corresponds directly to foot length (e.g., CN 240 = 240mm).
-
CN is NOT EU. Do not confuse a CN 40 with a European 40. The Chinese fit is typically shorter and narrower.
-
Material matters. Most CN-market footwear uses synthetic leathers that do not stretch. If you are between sizes, always go up.
-
Width is the silent killer. Asian lasts (the mold shoes are built on) are generally B-width. If you have a D-width (standard US) or wide foot, you must adjust your length calculation.
## The Logic Behind CN Sizing
Most confusion stems from expecting an arbitrary number system like we use in the States. The US system is archaic—it's based on barleycorns (yes, the grain). Chinese sizing is far more pragmatic. It is almost entirely based on the length of the foot in millimeters or centimeters.
The Two Main CN Formats
-
The Millimeter Code: You might see sizes like 230, 235, 240, 245. This is the literal length of the foot the shoe fits. If your foot measures 240mm, you buy a 240. Simple.
-
The Pseudo-Euro Code: This is the dangerous one. You see sizes like 37, 38, 39. It looks European, but the grading difference is usually 5mm per size, whereas standard EU sizing (Paris point) is 6.67mm. This means a CN 40 is significantly smaller than an EU 40.
Always check the detailed specs. If you are buying sneakers, cross-reference with our Sneaker Drop List to see if specific brands run true to this logic.
## Comparison: CN vs US vs EU
Visualizing the drift between these systems saves you money. Notice how the CN size tracks closely with millimeters, while the US and EU sizes drift apart.
| Foot Length (mm) | CN Size | US Women's | US Men's | EU Size (Approx) |
|---|---|---|---|---|
| 225 | 35 / 225 | 5.5 | - | 35.5 |
| 230 | 36 / 230 | 6 | - | 36 |
| 235 | 37 / 235 | 6.5 / 7 | 5 | 37 |
| 240 | 38 / 240 | 7.5 | 6 | 38 |
| 245 | 39 / 245 | 8 | 6.5 | 38.5 |
| 250 | 40 / 250 | 8.5 / 9 | 7 | 39.5 |
| 255 | 41 / 255 | 9.5 | 7.5 | 40.5 |
| 260 | 42 / 260 | 10 | 8 | 41 |
| 265 | 43 / 265 | 10.5 | 8.5 | 42 |
Note: This chart assumes a standard width. See the "Toe Box" section below for adjustments.
## The "CN 41" Problem
I see this constantly in my inbox. A client orders a CN 41 expecting it to fit like their trusty Birkenstock 41s. They arrive, and they can't even get their heel in.
Here is the math: A European 41 fits a foot roughly 260-267mm long depending on the brand. A CN 41 is built for a foot measuring exactly 255mm. That is a full centimeter difference. In shoe fitting, one centimeter is the difference between comfort and needing orthopedic surgery.
If you wear an EU 41, you likely need a CN 43. Always scale up when converting from EU to CN, never match the number directly.
## How to Measure for 2026 Online Shopping
Forget the old "trace your foot with a pencil" trick. The angle of the pencil adds 2-3mm of error. We need precision. Use our Shoe Size Converter (Intl) after you get these numbers.
-
The Wall Method: Stand with your heel flush against a wall. Ensure you are wearing the type of socks you plan to wear with the shoes.
-
The Fixed Object: Place a heavy book or box touching your longest toe.
-
The Measurement: Step away and measure the distance from the wall to the object in millimeters. Do not round down. If you are 242mm, you are 245mm in the CN system.
-
The Width Check: Measure the widest part of your foot. If your width exceeds 100mm (for women) or 110mm (for men), you typically need to size up one full CN size to accommodate the volume.
## Material Physics: Why Fabric Dictates Size
Fit is not just geometry; it is physics. The material composition of the shoe determines if you can get away with a snug fit.
-
Canvas/Knit: These have high elasticity. You can buy your exact CN measurement. (e.g., foot is 240mm, buy CN 38/240).
-
PU / Synthetic Leather: The most common material in affordable exports. It has zero give. It will not break in. If your foot is 240mm, buy CN 39/245. You need that extra 5mm for toe splay.
-
Real Leather: Rare in budget CN imports, but if you find it, you can size true to length as it will mold to your foot over time.
Also, consider the elevation. High arches push the foot forward in heels. Check the Heel Height Guide to understand how pitch affects functional length.
## Men's Sizing Anomalies
For men, the translation is rougher. The standard Chinese last is significantly narrower than the US D-width standard.
If you are a US Men's 10, you are used to a certain volume in the toe box. A CN 44 or 45 might match your length, but it will likely crush your pinky toe.
My recommendation: Unless the brand explicitly states "Wide Fit" or "Global Version," men should automatically size up two full CN sizes from their measured length. If you measure for a CN 43, buy the CN 45.
Buying footwear from overseas does not have to be a gamble. It is a calculation. By ignoring the arbitrary size numbers and focusing strictly on millimeter measurements and material composition, you can secure high-design footwear without the sizing heartbreak. Remember: measure twice, check the material elasticity once, and when in doubt, choose the larger size. An insole can fix a loose shoe, but nothing can fix a shoe that is too short.
Dive Deeper
Explore specific topics related to Chinese Shoe Size Guide: Converting CN to US Fit Mechanics:
