Black Diamond Helmet Size Guide

Not sure which Black Diamond helmet size to choose? Measure your head circumference and use the chart for your specific model to find the most suitable size.

Black Diamond does not use exactly the same sizing chart for every helmet. The Capitan, Vapor, Vision and Vector follow one chart, while the Half Dome uses a different size range.

How do Black Diamond helmets fit?

Black Diamond helmets are generally available in S/M and M/L. Each size corresponds to a head-circumference range measured in centimetres.

Some ranges overlap. If your measurement falls within the overlap, the best choice will also depend on your head shape, preferred fit and whether you plan to wear a thin beanie underneath.

Always use the chart for the specific model, as the Half Dome measurements differ from those used for the Capitan, Vapor, Vision and Vector.

How to measure your head circumference

Use a soft measuring tape and wrap it around the widest part of your head, approximately one inch above your eyebrows.

Keep the tape level above your ears and around the back of your head. It should sit against your head without being pulled too tightly.

Record the measurement in centimetres and compare it with the chart for your helmet model.

Black Diamond Capitan, Vapor, Vision and Vector helmet sizes

This chart applies to the Capitan, Vapor, Vision and Vector models, as well as versions that use the same construction and sizing.

On mobile devices, swipe horizontally to view all columns.

Black Diamond Half Dome helmet sizes

The Half Dome uses a specific size chart. Do not automatically choose the same size you wear in another Black Diamond helmet.

On mobile devices, swipe horizontally to view all columns.

What if you are between two sizes?

If your head circumference fits within both size ranges, choose the size that provides a stable fit without uncomfortable pressure points.

Once adjusted, the helmet should remain securely in place when you move your head, without slipping forwards, backwards or sideways.

If you intend to wear a thin beanie underneath, take the extra thickness into account when trying the helmet on. The helmet must still remain correctly positioned and secure.

How to check the helmet fit

Position the helmet level on your head, then adjust the rear retention system and chin strap.

The chin strap should be tight enough to keep the helmet secure without restricting breathing or jaw movement.

Gently shake your head in several directions. The helmet should move with your head rather than shifting independently.

Frequently asked questions about Black Diamond helmet sizing

Do all Black Diamond helmets use the same size chart?

No. The Capitan, Vapor, Vision and Vector use one sizing range, while the Half Dome has different measurements.

Can you wear a beanie under a Black Diamond helmet?

A thin beanie may be worn provided the helmet can still be adjusted correctly. Avoid bulky layers that could alter the helmet’s position or stability.

How can you tell if a helmet is too large?

A helmet is too large if it still moves after adjustment, drops towards your eyes or shifts when you shake your head.

How can you tell if a helmet is too small?

A helmet may be too small if it is difficult to put on, creates painful pressure points or does not sit correctly on your head.

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