How to Measure Your Head for a Cycling Helmet

 
 

What You'll Need

  • Soft measuring tape (fabric or flexible plastic)
  • Mirror
  • Someone to help (optional but recommended)

Step-by-Step Measurement Guide

  • Position the measuring tape about 2.5 cm (1 inch) above your eyebrows
  • Wrap the tape around the widest part of your head, just above your ears
  • Keep the tape level and snug, but not tight
  • Note the measurement in both centimetres and inches
  • Take the measurement 2-3 times to ensure accuracy

Pro Measuring Tips

  • Measure at the end of the day when your head may be slightly larger
  • If you have thick hair, consider how you'll wear it while cycling—long hair should be in your typical riding style (ponytail, bun, etc.)
  • For bike helmets for women with long hair, measure with hair positioned as you'll wear it
  • If you're between sizes, we recommend sizing up for better helmet fit adjustment range
  • No measuring tape? Use a piece of string, then measure against a ruler
Helmet size chart with head circumference and weight measurements

Additional Measurements

  • Measure head length from the center of the forehead to the furthest point at the back of the head
  • Measure head width at the widest point of the head, typically just above the ears
  • Take measurements in a straight line and avoid following the contours of the head
  • Having someone assist with the measurements can make the process easier and improve accuracy
Measurement chart for head size with a diagram of a head and red lines indicating measurement points.
Cyclist wearing a black PIKIO Si helmet

Why Proper Helmet Size Matters

  • A well-fitted bike helmet stays in place during impact, ensuring our OBLIK technology and impact protection features work as designed
  • Even the best rated bike helmet won't protect you properly if it's the wrong size
  • Proper helmet fit prevents pressure points and headaches during urban riding or long-distance cycling
  • Correct sizing ensures high airflow ventilation channels align properly with your head
  • The right lightweight helmet fit feels almost weightless and secure