We get a lot of questions that go something like this:
“Hi, the new [insert name of a particular ski] sounds exactly like what I’m looking for! I’m 5’9”, 180 lbs – should I go with the 184 cm or 177 cm length?”
There’s a good reason we get asked this a lot, because there is no truly reliable formula to determine what size of a given ski will unquestionably work best for you.
With so many different ski designs on the market, the correct ski size for you can differ quite a bit from one ski to the next. And it’s an important choice to get right, since the size of a ski plays a big part in affecting how a ski is going to perform.
(If you’re just starting out, and you’re unsure what kind of ski to look for in the first place, you might want to check out our 101 article, The Best Skis for Beginners, before continuing here.)
Skis no longer all have the same straight shape and fully cambered profile these days, so no chart can accurately tell you your ideal ski length for every given ski based on a static measurement like your height or your weight.
One graph from a certain online retailer suggests that at my height (5”8”) I should consider skis between the lengths of 160 cm and 180 cm. That’s quite unhelpful.
While I’m sure I could ski a 160 cm ski and be somewhat ok, I’ve preferred longer skis than that since I was about 15 years old (and the same height), and the chart doesn’t explain why I might opt for a longer or shorter length in a given case.
So in this GEAR 101, rather than just throwing a graph at you, we’ll present some important factors to consider when you’re in the market for a new ski and need to choose a particular size. This information will be especially helpful if you find yourself stuck in between two lengths of a given ski, unsure whether you should (or why you would) go with the longer or the shorter size.
The topics mentioned below mainly have to do with the design and performance of skis that we discuss in our reviews, and as will become clear, the topics are all related — there will be some overlap in thinking / principles from one to the next.
Where to Begin? Establishing a Baseline
We’ve just said there is no-hard-and-fast rule to determine what length of a particular ski you should go with, as there are now plenty of reasons a person might opt for a ski that’s longer or shorter than they may have say, 10 years ago.
If we’re talking about a traditional, fully-cambered ski, since the introduction of parabolic skis (i.e., skis with wide tips and tails and not-super-straight sidecut radii), the general rule has been that your ski should reach somewhere between your chin and the top of your head; a beginning skier was told to go with a ski length that leaves the ski tip closer to their chin, and a more experienced skier would typically go with a ski that reaches closer to the top of their head.
There is still some validity to that system today in that it ought to steer someone away from purchasing at the ski swap either a pair of snowblades or a 220 cm world cup downhill ski. But again, the rule assumes that you’re looking at a traditional, non-rockered, fully-cambered ski from about 1995. And if you’re shopping for a ski these days, you’re probably not looking at many non-rockered, fully-cambered skis (dedicated carving / groomer skis being some of the few exceptions). And even if you are, there are a number of good reasons why you might go with a ski longer or shorter than this older, overly simplistic system would suggest.
Rocker / Camber Profile & Running Length
Generally speaking, running length refers to the portion of a ski’s edge that’s in contact with the snow when you’re standing on the ski. In a sense, it’s a measure of how functionally “long” the ski is (i.e., how much of the ski is actually in contact with the snow when skied bases flat). Some people call this effective edge, others call it by some other name, but here, we’re just referring to it as “running length.”
On a ski with “rocker” or “early rise” in its tip and / or tail, the edge (along with the rest of the ski) comes off the snow sooner than it would on a traditionally cambered ski of the same length.
(See our Rocker 101: A Brief History of Rocker + A Glossary of Terms for a more in-depth discussion of rocker and ski camber profiles.)
Thus the total running length of a rockered ski is shorter than that of the ski with a traditionally cambered profile.
Caveat: technically, the running length of any ski is variable. For example, when you get a ski into soft conditions, some of the edge and surface area on the rockered portion(s) of the ski will come in contact with the snow surface, lengthening the running length. And when laying a rockered ski over into a carve on firm snow, depending on the ski’s sidecut and the curve of the rocker in the ski, you may engage more of its edge than is in play when it’s gliding with its bases flat on the snow.
The other term usually used to describe how “long” a ski feels is its “effective edge.” This is often used interchangeably with “running length,” though they’re different and, again, many people seem to disagree about what each of those terms actually means. For us, the effective edge refers to the distance between the widest point at a ski’s tip and the widest point at its tail, so it’s determined by the sidecut / shape of the ski, whereas the running length is determined by the rocker profile of the ski. So a ski with a lot of tip and tail taper (i.e., the widest points of its tips and tails are closer to the middle of the ski, not at the very ends) will have a short effective edge. That said, the effective edge and running length are often correlated since many skis with short effective edges also have deep rocker lines and therefore short running lengths, though there always some exceptions. What you should really focus on is the combination of (1) rocker and (2) taper — the more tapered and more rockered a ski is, the shorter it will feel compared to a minimally rockered, minimally tapered ski.
In general, a rockered ski will behave like a shorter ski on hard snow compared to a non-rockered ski of the same length, because you are skiing on a shorter edge as if you were on a shorter ski. So if you’re used to skiing a fully cambered ski that is, for example, 178 cm long, but the new very-rockered ski you’re looking at comes in a 178 cm length and a 184 cm length, you’re probably going to be better off going with the longer 184 cm length. The 184s will feel more like your old 178s on snow, given their reduced running length.
Examples: I’m perfectly happy skiing the mostly-cambered and minimally tapered 177 cm Head Monster 83 Ti, and I’m equally happy skiing the very tip and tail rockered and fairly tapered 190 cm Moment Wildcat.
In sum, the amount of rocker / running length and taper / effective edge that a ski has is very important to consider in conjunction with the actual material length of the ski. If you’ve been skiing a fully cambered pair of skis for years, and you’re looking at a new pair that has some tip and / or tail rocker, think about the running length of those skis rather than their material length.
Your old, fully cambered skis may have reached the bridge of your nose, and these new rockered ones may reach over your head, but if you size your new skis the same way you sized your old skis, your new skis will feel too short, twitchy, and unstable.
Speaking of which…
Stability & Instability
Another factor to consider when deciding on what length of a ski to go with is how stable and planted it feels on snow. How stable or “damp” a ski feels are things that we always cover in our reviews. If a ski is especially stable and exhibits good damping— i.e., it does not get twitchy or feel ‘noodly’ at speed or in bumped-up terrain — the more appropriate it might be to opt for a shorter length than you otherwise would.
Stability can serve to counteract the sometimes de-stabilizing effects of a rockered ski’s shorter effective edge.
Conversely, if a ski isn’t especially stable at speed (maybe it’s quite light, has a lot of sidecut, and / or is super soft), but you’d like to get as much high-speed stability out of the design as possible, you might consider going for a longer length.
- A Note on the Insufficiency of the English Language – “Damping” vs. “Damp”
For the grammar police out there, we are aware that “damp” means that something is “not dry,” while an object (like a ski, for example) might have good damping properties — i.e., the ski is not twitchy or reactive, but stable, smooth, and … damp.
Language is a tool to be used, not a system of unbendable rules. That’s why dictionaries have second, third, and fourth definitions of words. So we use the word ‘damp’ to mean stable / planted / not twitchy / not reactive. We do not mean that the ski is kinda wet.
While there are certainly exceptions to this statement, in general, the stiffer and heavier a ski is, the more stable it will be in rough conditions at speed, but the more demanding it will be in moguls and tight spots.
So if you’re considering a pretty stiff ski, but you are planning to ski a lot of moguls, opting for a shorter length might be a good move; in a shorter length, a stout ski will be easier to manage, yet will still provide some stability when you’re going fast.
And at the same time, a ski that’s particularly soft will often be more forgiving and less punishing than a stiff ski, so you may want to go for a longer length than you’re used to for the sake of gaining more stability at speed.
However, no matter how soft the ski is, the material length of a ski can still make it cumbersome in moguls, so sizing down a stiff ski is usually more appropriate than sizing up a soft ski if performance in either (a) big moguls with deep troughs, or (b) tight tree skiing in low-angle terrain is what you’re most interested in.
The longer the sidecut radius of a ski, the slower it will react when put on edge to arc a turn across the hill, and the longer that turn will be.
In this way, skis with shorter sidecut radii (e.g., ~14-18 meters) will be more responsive and easier to get on edge and turn, while skis with longer sidecut radii (e.g., ~24-32+ meters) will be more stable at higher speeds, especially in variable, rough conditions.
So if the ski you’re looking at has a long sidecut radius, you might consider choosing a length on the shorter side in order to make the ski more maneuverable, without sacrificing too much stability. For example, I like the 184 cm ON3P Wrenegade 108, which has a 26.8-meter sidecut radius (and is pretty strong and heavy), but I have little interest in skiing the 189 cm Wrenegade 108, which is heavier and has an even longer 27.5-meter sidecut radius.
As a generalization, the heavier a ski is, the more difficult it will be to pivot back and forth quickly. The lighter it is, the easier it will be to maneuver.
If you happen to know (from one of our reviews, perhaps) that a ski is not particularly quick, then sizing down will make it easier to handle, which will be important depending on where you ski (tight trees? big bumps? wide open terrain?) or how you like to ski (e.g., big turns at high speeds? smaller turns at moderate or slow speeds?).
Or if you’re looking at a light, highly maneuverable ski, you’ll be able to go with a longer length than you might be accustomed to gain some stability while still having a ski that will feel quick and easy to maneuver.
Flotation in Deeper Snow
The more surface area a ski has, the better it will plane up and float in deep snow. So if you’re looking at a ski that you plan to use in lots of fresh snow, you’ll get more float out of a longer length. Of course, the surface area gained by going with a longer length may be less important than the weight added to the ski or the decreased maneuverability, but it is a legitimate factor to consider.
And then you should think about the width of the ski, since that also plays an important role in flotation. E.g., the 184 cm Volkl Revolt 121 (a 121mm-wide ski) provides plenty of float in deep snow for me, and I don’t feel the need to bump up to the 191 cm version. But if I were to ski super deep snow on, say, the 106mm-wide Armada ARV 106Ti, I’d prefer to be on the 188 cm version rather than the 180 cm. That said, in many cases, length will play a larger role than width when it comes to float (especially if the width difference between some skis you’re comparing is less than ~10 mm).
How (and Where) Do You Actually Ski?
We touched on this above, but being clear about which sort of terrain you tend to ski to get down the mountain — or how you most often like to get down the mountain — will go a long ways toward helping you choose the right length of ski.
Do you like to make big turns while going very fast, or do you prefer a more dynamic, active approach to terrain and like to make more turns?
The faster you like to go (and the more open the terrain is), the more appropriate a longer ski will be; the shorter your turns are and the tighter the terrain you tend to ski (e.g., tight trees, steep moguls, etc.) the more appropriate a shorter ski might be.
For example, our reviewer, Paul Forward, loves the 184 cm Volkl Mantra 102 at his home mountain of Alyeska Resort in Alaska, where he is usually skiing more open terrain and rarely skiing moguls. But for the tighter terrain of Crested Butte, I like the 184 Mantra 102, but I’m confident that I personally would get along better with the 177 cm model. (It’s also worth noting that Paul weighs ~40 lbs. more than me.)
In a similar vein, the more concerned you are about how light and maneuverable a ski feels in the air for doing tricks and jumps, the more sense it makes to go with a shorter length. (I enjoy skiing the 184 cm Moment Wildcat for its in-air playfulness, but I also enjoy the 190 cm Moment Wildcat for its increased stability in chop.) Of course, as mentioned above, if the ski you’re considering also happens to be particularly light, then going with a shorter length may be less necessary.
Final Thoughts For Now
Hard and Fast rules are nice, but they are often too simplistic to be genuinely useful.
If this article seems to have complicated the topic more than cleared it up, we’re okay with that, because we think that you will be in a better position to understand and evaluate the numerous factors that go into answering the question, Should I go with this length or that length?
Still Have Questions?
If you do still have questions about which length of a given ski (or several skis) you should be considering — or if you have any questions about skis, ski boots, bindings, etc. — become a Blister member, send us an email, and we’ll be happy to get you sorted out.