Osias Size Guide
The Perfect Fit Guide 📏
Forget "sizing up 3 times." We engineered our costumes for real bodies.
The "Golden Rule"
Stop guessing. Start measuring.
Cosplay costumes fit differently than your daily hoodie. Most of our premium fabrics (uniform cloth, jacquard) do not stretch. To get that "canon" look, match your measurements, not your ego.
- Shoulder Width: Measure across your back from shoulder tip to shoulder tip.
- Bust/Chest: Measure around the fullest part. (Not your bra size!)
- Waist: Narrowest part of your torso. Critical for skirts/pants.
- Hips: Fullest part of your hips/glutes.

Which Chart Should I Use?
Check the Product Label or description to see if the item is "US/EU Sizing" or "Asian Sizing".
🅰️ Standard US / EU Sizing (Western Fit)
True-to-size fit designed for Western bone structures. No need to size up.
| OSIAS Size | US Size | Shoulder (cm) | Chest (cm) | Waist (cm) | Hip (cm) |
|---|---|---|---|---|---|
| S | 2/4 | 38 | 85 | 66 | 92 |
| M | 6/8 | 39.5 | 91 | 72 | 98 |
| L | 10/12 | 41.5 | 97 | 78 | 104 |
| XL | 14/16 | 43 | 103 | 84 | 110 |
| XXL | 18/20 | 44.5 | 111 | 92 | 120 |
🅱️ Asian Sizing (Petite Fit)
Runs smaller. We recommend sizing up 1-2 sizes compared to US brands.
| Size | Shoulder (cm) | Chest (cm) | Waist (cm) | Hip (cm) |
|---|---|---|---|---|
| XS | 38 | 84 | 64 | 88 |
| S | 39 | 88 | 68 | 92 |
| M | 40 | 92 | 72 | 96 |
| L | 41.5 | 96 | 76 | 100 |
| XL | 43 | 100 | 80 | 106 |
| XXL | 44.5 | 104 | 84 | 110 |
👨 Men's Standard Sizing
True-to-size US fit with broader shoulders.
| Size | Shoulder (cm) | Chest (cm) | Waist (cm) | Hip (cm) |
|---|---|---|---|---|
| S | 44 | 92 | 76 | 92 |
| M | 46 | 100 | 84 | 98 |
| L | 48 | 106 | 90 | 104 |
| XL | 50 | 114 | 98 | 112 |
| XXL | 52 | 122 | 106 | 120 |
Frequently Asked Questions
I am usually a Medium in Zara/H&M. What size am I?
If the product is marked "US Sizing", our Medium (US 6/8) is a perfect match. If it is "Asian Sizing", you will likely need a Large or XL.
My Bust is Medium but my Waist is Large. What do I do?
Always fit to your largest measurement. For dresses/jackets, prioritize Bust/Shoulder. For pants/skirts, prioritize Waist.
Do you offer custom sizing?
Currently, we focus on ready-to-ship sizes to get your gear to you fast. We do not offer custom tailoring at this time.