Rudy Project Bike Helmet Size Chart

1. Achieve the perfect fit by measuring your head circumference correctly.

2. Watch the video below to see how to measure your head correctly. (If you don’t see a video below, please refresh this page, or you might need to allow this website through your Ad blocker.)

3. VIDEO: How To Measure For A Bike Helmet

4. On the chart below, find the helmet model that you are interested in, then find your head measurement to see which size you need.

Rudy Project Bike Helmet Size Charts

Model Small Small/Medium Large
Airstorm Outlet
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
Boost 01
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
Protera Outlet
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
Protera+
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
Racemaster MIPS
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
Spectrum 51.1 – 54.9cm 55.8 – 58.7cm 59.6 – 61.5cm
20⅛” – 21⅝” 22″ – 23⅛” 23½” – 24¼”
Strym
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
The Wing
54.9 – 58.7cm 59.6 – 61.5cm

21⅝” – 23⅛” 23½” – 24¼”
Volantis
54.9 – 58.7cm 59.6 – 60.6cm

21⅝” – 23⅛” 23½” – 23⅞”