International conversions Nov 25, 2026 4 min read
Cycling Kit Size Conversion (US, EU Brands)
Cycling kit brands use different scales. Italian brands (Castelli, Assos) run small. UK/US brands (Rapha, Pearl Izumi) closer to true US. Race cut runs smaller than club cut.
The Chart
| Body Chest | Pearl Izumi | Rapha | Castelli (race) | Assos |
|---|---|---|---|---|
| 34-36" | S | S | M | S |
| 36-38" | M | M | L | M |
| 38-40" | M | M | L | M |
| 40-42" | L | L | XL | L |
| 42-44" | XL | XL | 2XL | XL |
| 44-46" | 2XL | 2XL | 3XL | 2XL |
FAQs
Why Italian brands run small?
Italian cycling baseline is European pro racer body type — lean, tall. American brands use broader baseline body. Castelli race jerseys at L fit US M body. Always size up 1 for Italian race cut.
Bib shorts vs jersey sizing same?
Within a brand, yes generally. But jerseys often fit looser at chest while bibs fit tight on lower body. If chest and waist are different sizes proportionally, you may need different jersey vs bib sizes.
Need this on your store?
Tailor Size Guide ships pre-built size charts for Shopify.