How to Adjust Your Ski Bindings to Fit Boots of All Sizes

When you're flying down the side of a mountain, you may be thinking more about your skis and boots first and foremost, but ski bindings may be one of the most important pieces in your overall ski setup.

"Ski bindings hold your boot to your ski and allow your boot to detach from the ski in a fall," Sam Cochran, rental manager and hard goods buyer for Sun Valley Resort in Idaho, tells LIVESTRONG.com. "This reduces the possibility of injury to the lower leg and is, therefore, very important."

Adjusting bindings to fit different size boots is common practice among ski rental shops and people that share skis. But there are limitations to keep in mind.

A binding on someone's personal skis can typically adjust approximately one size in each direction above or below what it was originally mounted for, Cochran says. Rental shops use adjustable plate bindings on their rental and demo ski equipment that can be adjusted to fit almost any size boot, but these are not typically sold for a personal ski.

"A binding has to be mounted to a ski based on the overall millimeter length of the boot," Cochran says. "The center of the boot should be over the centerline of the ski. Any deviation from this undermines the performance and safety of the ski."

For micro changes to boot sizes, you probably don't need to redo your bindings. Some bindings have the ability to do micro adjustments if you think 2mm makes the bindings too tight against the boot, but most of the time you shouldn't have an issue if there's that small of a difference between sole lengths.

If you're not sure if your bindings need to be adjusted, check with your local ski shop, Cochran says.

Not all ski boots will fit in every binding, Cochran cautions. "Newer boots use a Vibram sole on the boot called 'grip walk,' which makes it more stable for walking. Most newer bindings are 'grip walk compatible,' but when in doubt, your local ski shop can confirm that your bindings and boots are compatible."

It also depends on the type of boot and binding you are looking for. "If you are trying to use a pin binding — which is mainly used for backcountry skiing — you'll need a special boot that has pin capabilities in order to attach to the binding," says Jack Donahue, communications coordinator for Ski Butler, a full-service ski and snowboard shop delivering equipment rentals to ski resorts across North America and Europe.

If you're buying a traditional pair of ski bindings, there isn't really much that needs to be done to match to the boot. Although bindings and boots look different across companies, their actual dynamics are pretty universal, so all boots should be able to fit into all bindings.

If you're confused or unsure if your boot will work with a specific binding, Cochran's advice bears repeating: Check with your local ski shop. "They can confirm that your bindings and boots are compatible."

In short, you don't. (Or you shouldn't.)

"Don't adjust your bindings yourself unless you are certified by the binding company," Cochran says. In fact, even if you feel like your bindings are set perfectly fine, he recommends getting them looked at regularly just in case. "Plan on getting your bindings tested by a reputable ski shop annually."

Why is this so important? The test makes sure the binding releases according to industry standards and that your settings are appropriate for your size, weight and ski ability.

"There are indicators on the binding to show that the forward pressure is correct, and there is a numerical release scale on each binding that is based on your height, weight, skier ability, boot sole length and age," Cochran explains. This is an industry standard called DIN, which stands for "Deutsches Institut für Normung‌,‌" meaning "German Institute for Standardization."

In a word: Yes. Skiing with any DIN that isn't your calculated DIN number can be dangerous. It's designed to be the perfect sweet spot just for you that will keep you locked in when you need to and pop you out when you have to.

"A DIN setting that is too high will not allow your boot to release easily in case of a crash, and can result in a higher potential for injury," Cochran says. "Conversely, a too-low DIN setting can cause you to pre-release from the ski when you don't want to."

"If you've brought your skis to a shop then they should have mounted and sized properly based on your sole length, height and ability level," Donahue says. "If you feel like your bindings are loose in any way, I would immediately take them to a ski shop to get looked at."

He also stresses that you shouldn't be quick to change your DIN setting on your own. "If your local shop has set your DIN to a certain number, there's usually a reason behind it. And if you decide to change it at all, then that fall is on you and not your ski shop."

It will depend on your local shop, but Cochran says a ski mount costs about $50 on average and should include a binding test to ensure the safety of the binding.

But you'll likely get more out of it than just a remount. Both experts stress an important reminder: Your local ski shop is your friend. Lean on them for any questions or doubts you have when it comes to your equipment.

"These people are super knowledgeable about every aspect of ski setups and enjoy talking about it to anyone who wants to listen," Donahue says.