Ski Boot Buying Guide

Ski boots are, without a doubt, the single most important part of your kit. Your boots are the link between you and your skis. If they don't fit well, your skiing suffers straight away. Skiing is both better and more fun in a pair of well-fitting ski boots! What's more, the control that a properly fitted pair of boots gives you will genuinely make you a noticeably better skier.

One of the most common mistakes we come across is people skiing in boots that are too big. Strange as it may sound, a ski boot that is too large can cause both pressure points and cramp. This is mainly because your foot isn't held in place, so you end up tensing it. As a general rule, it's better for the boot to feel a little too tight the first time you put your foot in. That way, once you've skied it in – or we've helped you shape it – it has a better chance of ending up fitting your foot perfectly. It's usually better to start with a boot that's slightly too tight than one that's slightly too big.

Does it really matter that much if your boots are too big – can't you just do the buckles up a bit tighter? The simple answer is no. Ideally, you shouldn't need to buckle your boots particularly tightly. The best fit is when the boot fits so well that the buckles are mainly there to hold the boot together and fine-tune the flex. If you have to buckle your boots too tightly, you can easily get pressure points, because the boot no longer closes evenly around your foot.

Choosing the right boot for your alpine skiing can feel tricky. That's why we've put together this buying guide to make it easier for you to pick the right ski boot.

Choose the right ski boot size

Know how big your foot is. The easiest way to find out is to stand with your heel against a wall and trace around your foot on a sheet of paper. Then measure at the longest point – that's your size in cm. If, for example, you measure 25.2 cm, your size should end up at 25.5. That's no guarantee, though, partly because manufacturers measure slightly differently, and partly because there's more to fit than length. It also depends on the kind of fit you're after. It isn't unusual for someone who measures 25.2, for example, to choose a boot in 24.5 so that their foot is held really firmly.

Another measurement to consider is the last width. Using your tracing, measure the forefoot at its widest point – that's your last width. The last of a ski boot is measured in size 26.5. From there, as a rule of thumb, the measurement increases or decreases by 2 mm per size. So if, for example, your foot measures 27.5 with a last of 102 mm, you should look for a boot with a 100 mm last. It's always better to get the right last width than, say, to go up a size in the wrong model. Here too, the kind of fit you want plays a part. It's not at all unusual to choose a last slightly narrower than your foot if you want a precise fit. For the best fit, it's better to start with something a little too tight and create room where it's needed than the other way round.

Do you have a high instep? The top of the instep is often the most critical point for how a boot fits. You want the pressure to be evenly spread, with no sharp pressure down onto the foot. We'll help you find a model that fits and adjust it if needed.

Which flex should I choose?

Flex describes how stiff the ski boot is and, in practice, how much power you can transfer to your skis. A common misconception is that a stiff flex is always a good thing. In theory a stiffer boot does transfer more power – but only as long as you, the skier, have the strength and technique to generate it. If your boot is too stiff, the result is that you can't get any pressure through to your skis, which in turn means you lose edge grip and control. In other words, it's important to have a flex that suits you and the way you ski.

There's no reliable rule that says "this is the flex you need". There is no industry standard, which means two different brands with a flex of 110 can feel quite different. The number is more of a guide to the boot's stiffness. Flex is also affected by the plastic the boot is made from, the liner and the type of power strap fitted. One of the most important factors, and one that's often overlooked, is how much the fit itself affects the stiffness of the boot. A roomy or slightly oversized boot will always feel softer than one with a snug fit. That's because your foot moves around inside the boot before it can start driving power through to the shell.

Generally speaking, the right flex depends both on your skiing ability and on your weight. A heavier, more powerful skier needs a stiffer boot than a lighter one.

Should I choose a ski boot with a walk mode?

Today there are plenty of ski boots that combine a good walk mode with excellent stability on the way down. If you're going to be skinning uphill on ski touring trips or shorter tours off-piste, the choice is easy. Go for a boot with a walk mode that's compatible with tech bindings. It makes the climb far more comfortable without having to compromise too much on the descent.

But even if you're not planning any ski touring, a boot with a walk mode can be a good choice. You get solid downhill performance, and the feel on the snow isn't noticeably affected by the feature. The extra range of movement also makes it easier to walk between lifts or around the ski resort.

At the same time, it's worth bearing in mind that a pure alpine boot still gives you the most direct power transfer. If you're chasing maximum precision in every turn – as an advanced on-piste skier, for example – it may be worth choosing a traditional model without a walk mode. The difference is mainly noticeable in rebound and response, but usually only very experienced skiers can really feel it.

In short, it comes down to how you use your ski boots. Do you want versatility and comfort off the slopes too? Then a walk mode is a smart choice. Are you focused entirely on on-piste skiing and want absolute performance? Then a classic alpine boot is still the best option.

There are many models today that offer both a good walk mode and good stability when skiing. If you're going to be walking uphill, the obvious choice is a boot with a walk mode that's compatible with tech bindings. These days, though, you can choose a boot with a walk mode even if you're not planning a tour. Many models deliver great downhill performance, where your skiing isn't held back by the walk mode.

If you get into the fine detail of power transfer and performance, however, nothing beats a pure alpine boot. If you're a demanding on-piste skier, a walk mode doesn't really serve any purpose. Some differences in rebound and power transfer can be noticeable, especially if you're a really strong skier. Most of us mere mortals probably won't notice much difference. Either way, the key is to be clear about how you'll use your boots and to buy the right kit.

Custom-moulded footbeds for the best fit

To make the fit even better, we recommend a custom-moulded footbed. This means replacing the insole in your boot with one that we mould to your foot. The idea of a custom-moulded footbed is to support your foot and spread the pressure more evenly. The moulding supports all of the arches of the foot. You might think the inner arch is the only one affected, but that's not quite the case. It's certainly the most obvious one, but we also have an outer arch further back towards the heel bone, as well as a transverse arch across the base of the toes. They are all affected differently by load, and by how much varies greatly from person to person.

The moulding is done with the foot in a relaxed position, which stops the foot from changing shape too much under load. A foot under load often becomes both longer and wider. Add pronation and supination – the angling that happens at the ankle joint – and it's easy to see what a footbed can do. It's not unusual for a footbed to make such a big difference that you can actually go down a size.

If you overpronate – meaning your ankle rolls inwards – this can create pressure points, both on and around the ankle bone and on the outside of the foot. When this happens, it's easy to feel that the boot is too narrow. Supporting the arch with a footbed stops the foot from collapsing inwards, which in turn relieves those pressure points.

A footbed that takes the strain off your foot also improves blood circulation. That means your feet don't tire as quickly, and they actually stay warmer too. More even, better blood flow combined with relaxed feet also helps prevent the cramp that can occur when ski boots don't fit properly.

We are ski boot specialists

We're passionate about skiing and ski boots. The best thing you can do is come and visit us in the shop. We'll help you measure your feet and find a ski boot that suits you and the way you ski. We have a fully equipped boot-fitting workshop and can adjust your boots whenever needed. So you're very welcome to visit us in the shop at Isaberg – we'll help you find the right ski boots for many great days on the slopes to come.

Can't make it to the shop? Of course we can also advise you by email or phone! Just get in touch – we'll be more than happy to help!