GymBum UK Size Guide

🧡 GymBum UK Sports Bra Size Guide

Size Chest (inches) Underbust (inches)
XS 33 ⅛ 27 ½
S 34 ⅝ 29 ⅛
M 36 ¼ 30 ¾
L 39 ⅜ 33 ½
XL 42 ½ 36 ¼
2XL 45 ⅝ 39
3XL 48 ⅞ 41 ¾

🧍♀️ Women’s Activewear

UK US EU Asian Tops / Bras Leggings / Shorts Trainers (UK/EU/US)
4–6 0–2 32–34 S XS XS 3.5 / 36 / 5
8–10 4–6 36–38 M S S 4–5.5 / 37–38 / 6–7.5
12–14 8–10 40–42 L M M 6–7.5 / 39–40 / 8–9.5
16 12 44 XL L L 8–8.5 / 41–42 / 10–11
18 14 46 XXL XL XL 9–9.5 / 43–44 / 11.5–12

🧍♂️ Men’s Activewear

UK US EU Asian Tops / Hoodies Shorts / Joggers Trainers (UK/EU/US)
S S 46 M 36–38" Chest 30" Waist 6–7 / 39–40 / 7–8
M M 48–50 L 38–40" Chest 32–34" Waist 8–9 / 41–42 / 9–10
L L 52 XL 42–44" Chest 36" Waist 10 / 43–44 / 11
XL XL 54 XXL 46–48" Chest 38" Waist 11 / 45–46 / 12
XXL XXL 56 3XL 50–52" Chest 40–42" Waist 12–13 / 47–48 / 13–14

🧵 Fit Notes

  • Asian sizes typically run 1–2 sizes smaller than UK sizing.
  • For a performance fit, choose your regular UK size.
  • For a relaxed fit, size up.
  • Measurements are approximate and may vary slightly by fabric and style.

Fit Tip: Some of our activewear follows Asian sizing (approx. 1–2 sizes smaller than UK). Refer to the GymBum Size Guide for accurate conversions.