Bike Helmet Fit and Size Guide

Your helmet is your most important accessory. Liv helmets are designed for all types of women riders, wherever they are in their cycling journey. From road and triathlon, where speed and aerodynamics matter most, to trail riders looking to push the limits on every ride and city riders who want a stylish look. Each one is built on thoughtful designs and ride-specific technologies to keep you cool, comfortable and secure on roads, paths or trails.

Bike Helmet Safety Tips

  • Technologies like Mips (Multi-directional Impact Protection System) can help reduce the chance of brain injury.
  • If you’ve had a crash wearing your helmet, replace it. 
  • Even if you haven’t had a crash, replace your helmet every few years with regular use. 

How to properly wear a bicycle helmet

  • Loosen ratchet strap at the back of the helmet. 
  • Make sure the helmet is sitting level on your head, and low on the forehead. Place two fingers above your eyebrows. If your helmet is lower or higher, adjust. 
  • Tighten ratchet strap at the back of helmet. Shake your head, the helmet should not move.
  • Make sure the side straps form a “V” shape around your ears. 
  • Make sure the chin strap is tight. You should be able to fit two fingers between the strap and your chin. If there is too much space, tighten the strap.
Helmet Sizing

Helmet Size Guide

Ensuring you purchase the right size helmet is not only a matter of comfort, it is a decision that can impact your safety. Our helmet measurements refer to head circumference. Use a tape measurer and follow the diagram to confirm the circumference of you or your child’s head and choose the correct helmet to match.

Step 1 (A): Place the tape measurer about 25 mm above your eyebrows.

Step 2 (B): Ensure the measuring tape is about 15 mm above your ear.

women's helmet fit

Adult Helmet Sizing

girl's helmet sizing

Youth Helmet


Child Helmet

UniversalChild Universal50-55cm4-10

Toddler Helmet

UniveralToddler Universal46-51cmUnder 5