Boots are the single most important component of your ski setup and it’s worth spending extra time and energy to get the right boot with the right fit. Your boots are your only way of translating your body’s intentions to your skis, so a precise fit is important for control and performance. The goal in ski boot fitting is to find a size and shape that you’ll be comfortable in without compromising too much performance.
Everyone’s foot is unique, so there is no one “right” way to fit boots. The size, shape, flex and features of your ideal boot will vary depending on ability level, aspirations, height and weight, frequency of days on the hill, and other factors. Because of their construction and the job they have to perform, ski boots will never be as comfortable as street shoes and you shouldn’t try to fit them the same way. Remember that the foam used for padding inside the boot will compress with use, so what seems like a very snug fit in a new boot will become more relaxed after just a few days of skiing.
Here are some things you’ll want to consider when choosing boots:
Your skiing level is definitely going to give you an idea of what type of fit, flex and features to look for in a ski boot. We’ve broken skier types into three groups based roughly on ability:
Beginner / Intermediate. You prefer green and blue runs and typically like cruising on groomed terrain. You’re still working on mastering the mechanics of the sport, but are making regular progress. The best option for beginner/intermediates is a softer to medium flexing boot and a fit that will allow them to be comfortable all day long.
Intermediate / Advanced. You enjoy a variety of speeds and conditions, including moguls and steeper terrain, and require more precise steering and control from your boots. You ski blue and some black runs, cruise groomers with confidence and experiment with off-trail terrain. Intermediate/advanced skiers often have several years invested in the sport and should look for a medium flexing boot with a fit that’s precise enough to allow full control in a variety of conditions.
Advanced / Expert. You ski the entire mountain in all conditions with confidence. You easily make the transition from designated trails to off-piste in a variety of snow conditions including deep powder, crud, ice and moguls. You should be looking for a boot with a stiff to very stiff flex and a very precise fit. Note: Expert park and pipe skiers often prefer a roomier fit and softer flex in their boots compared to "traditional" experts.
Slight to moderate pressure on your longest toes when the boot is buckled and your leg is in an upright position is usually an indication that the boot will be the right size after some use. If the boot feels too short, try flexing the boot hard with the uppers buckled – drive your knee forward into the tongue several times with force. This will push your heel back into the heel pocket of the boot and create more space in the front - you should feel little if any pressure on the toes while flexing the boot forward. Check the fit of the liner with it out of the boot shell to see if the source of the pressure is the toe of the liner rather than the hard plastic shell – if so, this can usually be stretched by your shop. All ski boots will fit looser after a few days of skiing, and your object is to have a perfect fit at the end of the season rather than when the boot is brand new. Keep in mind that while it’s usually possible to enlarge a boot that’s a little too small, it’s virtually impossible to shrink a boot that's too big.
The length of your boot isn’t your only fit option. Like feet, every ski boot interior has a unique shape. Most manufacturers of alpine boots now make two or three distinct models or “lasts” to fit various types of feet. Generally, these lasts can be divided into narrow, medium and wide, and are based on the width of the forefoot measured on a slight diagonal across the metatarsal heads. Lasts with a wider forefoot normally have increased interior volume elsewhere in the boot as well.
Narrow Last. Narrow lasted boots normally have a forefoot width of 97 mm to 98 mm, and are quite narrow through the midfoot as well. These boots are best for people with narrow and low volume feet.
Average Last. Average lasted boots have a forefoot width of around 100 mm. These boots fit average feet well out of the box, and have a more relaxed fit through the midfoot and heel than narrow lasted boots.
Wide Last. Wide lasted boots are best suited to skiers with wider and higher volume feet, and typically have a forefoot width of between 102 mm and 106 mm. If you know what width you normally take in a street shoe, you may be able to pick which of these forefoot models most closely matches your foot. An “A” or “B” width foot, for example, usually works best in a narrow lasted boot, while a “C” or “D” width normally fits an average last of around 100 mm. Skiers with an “E” or wider foot should look for a wider, 102 mm or wider last. As with boot lengths, the forefoot width is not an absolute standard among different boot manufacturers, and each has their own formula for determining other dimensions inside the shell, but this is a good general guideline.
Boot manufacturers often build more than one model or flex using each last, so if you can find a boot that fits well but the flex isn’t right for you, look to see if it’s available in a softer or stiffer version.
Flex in ski boots refers to how difficult it is to flex the boot forward. Boot flex ranges from very soft to race stiffness, indicated by a numeric “flex index” that’s usually a number from 50 (soft) to 130 (very stiff). Often this number is written on the outside of the boot cuff. The method of determining flex index is not standardized between boot manufacturers, and one company’s 100 flex boot may not equal another company’s 100 flex boot, so use the numbers as a starting point but don’t get too hung up on them. Also, some companies use a 1-10 scale to for their flex rating, which is why we characterize flex as soft, medium, stiff, or very stiff in addition to giving a number rating.
Beginner-Intermediate men’s boots range from about 65 to 80 flex index, with Intermediate-Advanced boots going from about 90 to 100. Advanced-Expert boots normally are in the 110 to 130 range. The stiffest race boots are rated at 140 to 150, which is far beyond what most skiers need or want and usually reserved for high level competition skiers. Again, since there is no industry standard for measuring flex, it’s best to use flex index only as a general guide to choosing which model you’re interested in or as a way to compare models within a single brand.
Terrain, speed and type of snow play a role in choosing your flex as well. Pro level Freeride and Big Mountain skiers often choose a slightly softer boot than top World Cup racers, and pro park skiers go softer yet. Variable snow and very steep terrain often demand a bit more cuff movement, while a hard and uniformly smooth surface (like a race course) and techniques that demand tip pressure require a stiffer flexing boot. Personal preference and physical makeup are equally important. An athletic beginner may do just fine in a medium to stiff boot, and some expert skiers prefer a moderate flexing boot to a very stiff one.
Your height and weight are also contributing factors in choosing the best flex. Someone who is short and light doesn’t put as much leverage on a ski boot and a very stiff boot will limit natural body movement, while someone who is larger may require a stiffer boot, even if they are new to skiing. Keep this in mind if you are smaller or larger than average.
Matching the cuff to the size and shape of your calf is an important part of your ski boot fit. The shape and height of both the shell and liner cuff can be a big consideration for women (whose calves are generally lower and proportionately larger than men) or those with very large calves. If the upper buckles on a boot are extremely tight out of the box, most boots have upper buckle ladders that can be moved to several different positions, sometimes with a screwdriver or allen wrench, to give you more adjustment range.
Most manufacturers are now offering women specific boots that are designed to fit larger and lower calves, and many women’s models offer an adjustable cuff that will flare out to give you more fit options.
- Forward Lean & Ramp Angle
Alpine ski boots normally have a fixed forward lean of between 11 degrees and 18 degrees from vertical. Most modern boot designs reflect the shift in ski technique toward a more upright style and have less forward lean than boots of a few years ago, but the forward lean that works best for each skier is highly personal, and most boots have some adjustment capability. Often this involves installing or removing a spoiler or shim in back of the calf. Alpine touring boots commonly come with two forward lean options.
Ramp angle, or the angle of the boot board (bottom interior of the boot) relative to the ski, is normally fixed as well, but can sometimes be adjusted by a bootfitter or by installing shims under the bindings or wedges between the bootboard and liner. Some skiers are more sensitive to ramp angle than others.