Size Guide

adies & Gentlemen, we've crafted the ultimate size guide for your new favorite boxers, thanks to your feedback.

Don’t be surprised if you find yourself thinking, “Wow, I’ve never gone this big before!” Yep, our sizes tend to be more snug, but trust the guide—it’s your best bet for a great fit.

Still unsure? Reach out to us! No question is too small when it comes to perfect fit!

BioFit Size Guide – Original (CM)

(Normal leg, everyday fit)

Size Waist (CM) Leg Opening (CM) Length (Side Trouser Length CM)
S 68–76 18.5 22
M 76–82 19.5 23
L 82–88 20.5 24
XL 88–94 22 25.5
2XL 94–100 23 26.5
3XL 100–106 24.5 27.5
4XL 106–112 25.5 28.5
5XL 112–118 26.5 29.5


BioFit Size Guide – Original (Inches)

(Normal leg, everyday fit)

Size Waist (Inches) Leg Opening (Inches) Length (Inches)
S 26.8–29.9 7.3 8.7
M 29.9–32.3 7.7 9.1
L 32.3–34.6 8.1 9.4
XL 34.6–37.0 8.7 10.0
2XL 37.0–39.4 9.1 10.4
3XL 39.4–41.7 9.6 10.8
4XL 41.7–44.1 10.0 11.2
5XL 44.1–46.5 10.4 11.6


BioFit Size Guide – 2.0 (CM)

(Longer leg, more coverage)

Size Waist (CM) Leg Opening (CM) Length (CM)
S 68–76 19.5 32
M 76–82 21 33
L 82–88 22 34.5
XL 88–94 23 35
2XL 94–100 24 36
3XL 100–106 24.5 37
4XL 106–112 25.5 39
5XL 112–118 26.5 40

BioFit Size Guide – 2.0 (Inches)

(Longer leg, more coverage)

Size Waist (Inches) Leg Opening (Inches) Length (Inches)
S 26.8–29.9 7.7 12.6
M 29.9–32.3 8.3 13.0
L 32.3–34.6 8.7 13.6
XL 34.6–37.0 9.1 13.8
2XL 37.0–39.4 9.4 14.2
3XL 39.4–41.7 9.6 14.6
4XL 41.7–44.1 10.0 15.4
5XL 44.1–46.5 10.4 15.7

BioFit Size Guide – BIOFIT ORIGINS

(More leverage, more presence)

Size Waist (CM) Waist (Inches) Leg Opening (CM) Length
2XS 56–60 22–24 19 26 cm
XS 61–66 24–26 20 26 cm
S 70–76 28–30 21 26 cm
M 76–81 30–32 22 27.5 cm
L 83–88 33–35 23 29 cm
XL 91–101 36–40 24 30.5 cm
2XL 106–112 42–44 25 32 cm
3XL 112–118 44–46 25 32 cm