Bootfitting Guidance
The three principles of ski boot fitting
Oversized ski boots cause heel slippage and toe impact. Here is how bootfitters determine proper shell sizing.
Principle 1: never buy your street shoe size
Street shoes are built with roughly 12 to 15 mm of forward clearance so your toes do not contact the end while walking. If you purchase ski boots with that much room, your foot slides inside the plastic shell during turns.
To compensate for foot slippage, skiers often overtighten the instep buckles. This restricts blood circulation to the toes and causes toe impact against the front bumper during descents. A properly fitted ski boot fits more snugly than daily sneakers.
Principle 2: understand liner compression
Ski boot liners use dense foam that compresses to the contours of your foot. Over the first 4 to 6 full days on the mountain, a new liner compresses by 15% to 20% in volume. A boot that feels roomy in the showroom will feel loose after initial days on snow.
Principle 3: how to perform the shell fit test at home
Confirm your boot shell size before using your boots on snow:
- Unbuckle the boot completely and remove the soft inner liner from the plastic shell.
- Step your foot in thin ski socks directly into the plastic shell.
- Slide your foot forward until your longest toe touches the front of the shell.
- Examine the gap between your heel bone and the back of the plastic shell. One finger (approx. 10 to 15 mm) indicates a performance fit. Two fingers (approx. 20 to 25 mm) indicates a comfort fit. A gap exceeding 25 mm indicates the shell is too large.