On Cloudultra Pro Review: Can’t Rattle This Snake

Introduction to the On Cloudultra Pro

TAYLOR: Small-town living has its many perks. As much as that first sentence warrants an annual Better Homes issue, this isn’t the place to start a list. Some could argue there are equally as many bullet points on the downside.

The worst of it all is the drama. Intentional petty controversy is a form of entertainment. Nowadays, any onlooker can grab their popcorn and park it on the couch for a front-row seat to the ridiculousness. I can’t say I’ve ever been the source of, nor do I indulge in poking the bear to these pothole conversations, but I’m going to test out the formula here and now.

Here we go… On has never really had a noteworthy trail running shoe.

Did that send a controversial ripple out? Or am I in the clear because it’s mostly true? If this were an online chat platform, I’d leave the comment there for three days and then respond sidehandedly with untrue facts and digital sass. But it’s not, so let me elaborate.

Notice that I’m not saying that their trail offerings have been poor; however, over the years, there has yet to be an On trail shoe to grace our BIG awards. There has been no groundbreaking tech that adjusted the arc of trail footwear design. I haven’t even had a shoe that I’d recommend to someone, besides maybe the road-shoe-turned-trail-shoe Cloudsurfer Trail. There is simply nothing that has stuck out among the masses.

As we’ve seen on the road side, I knew we would have to wait… and wait… and wait, but eventually, On would be on the scene with something to ooh and ahh about. I’m elated to say that (for now) my zooming in on granulated Instagram pictures has halted because we finally have our feet in the On Cloudultra Pro.

Spoiler alert: This is the one that changes things.

REESE: When I tested the On Cloudultra 2 in 2023, it was the first time I had ever considered On as a trail running shoe. I had always assumed they were geared more toward the streetwear, athleisure vibe, likely because it was the primary shoe brand I’d see at the airport. I mean, these shoes were everywhere. The Cloudultra 2 was a fine enough shoe. They definitely made some interesting design choices, but I have to say, I relegated the shoe to my casual shoe line, and it’s been going strong for a year and a half. Talk about a great shelf life. But it never made it into my daily rotation of favorite trail shoes.

I hadn’t thought much more about On trail shoes since 2023, but I figured they were trying to hop on the trail bandwagon. I would have guessed that if they were up to something big in trail running, it would have happened by now. Well, June 2025 is their “now.” The On Cloudultra Pro feels like the designers weren’t just sitting on the bandwagon after all, no, no, they were out there getting all the data points on what makes a great shoe. And like Taylor alluded to, I think they’ve done something pretty damn good with this shoe.

Reader, be aware that like Michael, I too was not able to put in quite as many miles as I would have liked in this shoe. The day after it arrived, I was running in other shoes, five miles into a 20-mile run, and I incurred quite possibly the worst ankle sprain of my life. My ankle ballooned to the size of a baseball, and I had to limp back to my car. Shortly thereafter, I proceeded to have a minor meltdown, followed by a week of Normatecs, icing, and bike riding.

I’m back to mostly good but taking it easy. So I haven’t logged a multi-hour run in this shoe yet because I haven’t been able to run for more than an hour yet. I don’t know what’s happening with the Dirt Division this June, but sheesh, we need a vacation from ourselves.

MICHAEL: Taylor need not worry about spilling the tea we’ve all been sipping for quite some time. He’s absolutely right… over the years, On has been slow to bring their A-game to the trails, even whilst making huge strides on the pavement. Well, that all changes with the Cloudultra Pro, which features some of their top-of-the-line tech (most notably their premium Helion HF midsole foam) to achieve trail notoriety never before seen for this stylish Swiss brand.

Before we get to the review, I should mention that my miles in this shoe were unfortunately cut short, seeing as how I was bitten by a timber rattlesnake whilst donning them. By the Lord’s kindness, it was a dry bite, and I’m totally fine. But let’s not get sidetracked here, because this wildly improbable event really opens up a whole host of more important topics for us to discuss.

For instance, did the stack height of the Cloudultra Pro cause the bite to be perfectly placed, saving me from further catastrophe? Or rather, did the awesome styling of the shoe instill some manner of an unpleasant disposition in this serpent’s heart as I trotted along past it, causing it to lash out in a jealous fit of rage? These are the questions the trail running world desperately needs answers to, and as far as I know, we’re the only website with answers informed by real-world snake testing. So, without further ado, the On Cloudultra Pro.

What we like about the On Cloudultra Pro

TAYLOR: Efficient — a word you’ll read plenty of times within this review. Everything about the design of the On Cloudultra Pro is oriented toward making each step as smooth and as effortless as possible. That’s a tall task for a trail racer, especially over various conditions.

Plenty of shoes use the recipe of sandwiching a plate between a couple of layers of foam. The Hoka Tecton X 3, Adidas Terrex Agravic Speed Ultra, Rossignol Vezor, and Nike Ultrafly are just a few. Each has a slightly different take on how that works best, but it’s essentially the same design as the On Cloudultra Pro.

A good reason why this recipe is popular is that it works. On simply found a way to make it work to an impressive standard. Each layer brought something to the table that created a balance that I haven’t quite felt in a shoe before. And I don’t mean “balance” in the sense that each characteristic is moderated to a mid-degree. All aspects are fairly tuned up and work harmoniously.

Underfoot, the Cloudultra Pro uses two layers of On’s Helion HF hyperfoam. It’s the same compound found in the Cloudboom Strike and Cloudmonster 2 — some of On’s top-performing road offerings. The top layer is the softer, more cushioned, and more responsive of the two. It had a really nice step in feel and a noticeably high energy return. The lower unit of Helion HF foam takes on similar properties but is slightly firmer. Ideally, it would provide more structure and stability to the ride to support running over a variety of terrain and distances, and it does quite impressively.

The x-factors in the recipe are the trail-specific Speedboard and Cloudtec (the little holes in the midsole). Of course, a Speedboard isn’t new to the brand. The one used here is more X-shaped, with two fingers reaching through the forefoot and two extending toward the heel. They meet in the midsole, but I should clarify that the material is higher-quality nylon as opposed to carbon fiber. To me, this suggests that the plate is more there for lightweight stability than proper bounce.

While this plate works in tandem with the moderately aggressive rocker to maintain shape and promote uber-efficient toe-off, the Speedboard is going to be most effective at stability, like with the Hoka Tecton X 3 and the North Face Vectiv Pro 3. It is one of the only ways to really keep you upright and confident with these super foams underfoot.

I noticed the Cloudtec (the holes I mentioned) on downhill segments and anytime my foot struck firmly in the midfoot (i.e., uptempo effort). I could actually feel each cloud compress and release as my foot would land and roll through my gait cycle. A big concern is always getting rocks within the clouds, but that never happened here in the Rockies. Since it didn’t happen to me, it likely won’t happen in any other condition either.

The upper was quite complementary to the underfoot recipe. Even though it is a lighter engineered mesh, it is refreshingly not too light. Many racers try to cut any corner they can to save weight, and there’s always a likelihood that it will then lack in a different area, but I didn’t notice anything like that in this shoe.

Fit seems to be a high priority in the Cloudultra Pro, which runs true to size. Case in point is the toe box being slightly broader. It is more rounded compared to many race models, and I really appreciated that over longer runs in the Cloudultra Pro. I wouldn’t say it was wide, but it had a very “average” forefoot width that would accommodate many foot shapes.

At the same time, I was able to lock both the heel and midfoot down to a satisfactory level for most terrain. I was surprised at the overall ability to have a secure fit without strangling my feet. Multiple aspects play into this, like the upper material choice, serrated “race-lace,” and the higher heel collar construction.

Lastly, the new Missiongrip formula and versatile outsole design gripped well in most conditions. The fairly shallow lugs also allowed for smooth transitions between surfaces.

REESE: By the looks and materials of the Cloudultra Pro, it’s clear On has been doing a lot of work on their trail shoes. Just by looking at this shoe, it’s clear this is a race day shoe. If there is any doubt about that, one only needs to pick up the Cloudultra Pro and feel how light it is. To that end, let’s start with the upper. On went with a new material I’ve not seen before. It felt like in the past year, a lot of companies were leaning into recycled PU-coated weave uppers like the Matryx Micro on the Arc’teryx Sylan Pro, or the Motion Wrap on the Asics Metafuji Trail.

The upper, comprised of Leno weave, is incredibly light. I mean, you can see through to your sock. It’s patterned to provide just enough protection in all the right areas while allowing for a lot of air flow. It’s fairly durable and super great for hot days (cue scenes of Javalina and WS100). I can’t forget that the laces are the only option any company should ever choose when selecting laces. Braided laces are hands down the best. Challenge me, I’ll wait. They stay tied even when single-knotted.

Moving down, the midsole is terrific. I wish I had been able to log some multi-hour runs in this shoe to really put it through its paces, but I think I’ve got a pretty good feel of it. It definitely feels like a shoe that can go the literal and figurative distance. A shoe that will keep your feet feeling fresh(ish) well into a 50+ mile race. This is because On nailed the materials with their Helion HF Dual midsole.

On top, they’ve put a softer compound layered in what they call a “propulsion speed board,” but I just think of it as an X-shaped plate. Below it is a slightly stiffer foam. The effect is a shoe that offers a plush ride but doesn’t totally lose integrity or cause the foam to crumble.

If anyone recalls Hoka models from 2013, you’ll remember how soft the foam was. I’d just watch people’s shoes and legs kind of collapse inward as they ran. None of that is happening here. The rocker is subtle but appreciated. It’s not as notable as, say, The North Face’s Vectiv Pro, but you can feel a little propulsion from it. I’m just so impressed at how far of an advancement this shoe is compared to the Cloudultra 2. This shoe has legit character and a great feel.

The outsole on this shoe is exactly what I’d expect from a trail race shoe. Its Missiongrip rubber is strategically placed to balance weight and traction. I’m curious to see the longevity of the outsole; it feels like there is more exposed, softer foam on the bottom of this shoe than in other trail shoes. Nevertheless, the Missiongrip rubber is pretty darn good. I didn’t have much of an issue on any of the trails I ran on. I have some gripes about the performance in tech terrain, but that doesn’t have much to do with the materials.

MICHAEL: Much has been said about the burgeoning success of the Cloudultra Pro, and I concur with all of it, so I’ll just touch on a few of my personal highlights here. For starters, the plate situation in the Cloudultra Pro is totally fantastic. Sandwiched between two layers of highly supple, yet bouncy Helion HF foam is On’s take on the oft-fallible “Carbon plate in a trail super shoe,” called the Speedboard. And before you allow this hackneyed marketing jargon to call you back to the days of when we described On’s road shoes as two-by-fours strapped to your feet, allow me to elaborate.

Here, the TPU speedboard offers a very tasteful pairing of economy-boosting stiffness and stability with an adaptable flexibility that doesn’t hold the shoe back over rough terrain, resulting in a highly efficient, tuned feeling that truly blends the trail adaptability from recent plate-less trail super shoe concepts like the La Sportiva Prodigio Pro with the highly efficient (and protective underfoot) of the stiffer plated models like the Nike Ultrafly.

We’ve seen brands repeatedly try to dial in each of the plate “tuning knobs” for stability, propulsion, efficiency, and protection, yet after all of their attempts, none of them seem to strike a balance quite like the Cloudultra Pro. That, in my mind, is a huge success.

Like Taylor and Reese, I also really enjoyed the highly responsive, lightweight, and scary-fast feeling underfoot from the Helion HF foam. Even when I was hiking back on the trail from being attacked by a “danger noodle,” this shoe was pleasant to step into and returned energy as I hobbled along, trying to keep my heart rate down. Landings are soft, and toe-offs are highly propulsive. What more could you ask for on race day?

Also, I should mention that I was really impressed by the performance of On’s new Missiongrip formulation and lug pattern on this shoe. Despite a slightly lower profile lug, this outsole punches above its weight, stretching its technical limitations. In my estimation, one could comfortably race the Cloudultra Pro on any trail that would otherwise be suited to a Hoka Speedgoat or Tecton X. Maybe I’m overstating its abilities a little bit there, but it did handle the rattlesnake attack without a hitch, and if that’s not something worth giving technical cred for then I don’t know what is.

What we don’t like about the On Cloudultra Pro

TAYLOR: I’m originally from Minnesota. One of my favorite commonly used phrases from the motherland is, “That’s different.” Oftentimes, it is either used to share that you don’t know how you feel about something or that you don’t want to say you dislike something to someone’s face. This gig has actually helped me be more appropriately analytical. The “bad” parts of the On Cloudultra Pro fall into the first definition of “different” explained above.

One component that will inevitably be “different” for runners is the higher ankle collar construction. I’m not here to complain about it, other than that it was funky at first. It took a little getting used to. I wear crew-length socks and didn’t experience any Achilles rubbing or irritation. I feel that the construction benefited the package, and I mostly forgot about it once I started running.

Overall, the Missiongrip outsole performed quite well. The only times I noticed small slips were on wet rocks and roots.

Lastly, I think perception could harm the overall view of the Cloudultra Pro. Many will be expecting a high-energy racer. While it does have a noticeably smooth and efficient ride, it’s not exactly zippy like a marathon race day shoe would be. It is certainly responsive because it can roll with a range of paces. While I think this design was very appropriate for the target distance, some will inevitably be dissatisfied.

REESE: Back in 2023, I noted that the Cloudultra 2 ran a little small, and I needed a size US W8, a half size larger than I normally wear. So, of course, that’s the size I requested this go around. But it appears that On didn’t just do some fixing of the performance of the shoe, but they did change their sizes up a bit. It now runs true to size (On, please send me a US W7.5, I want to run in this shoe more).

Maybe it’s not something I dislike about the shoe, but it’s worth noting if you’ve run in On shoes before. Also, it’s worth bringing up since I did find the toe box to be a bit of a strange fit. But before I get to that, let’s talk about my biggest gripe. And by biggest gripe, I mean, it’s actually not a deal breaker. I just think it needs some tweaking. I want this shoe to be the best shoe possible.

The platform of the shoe is kind of the only thing I’d consider changing. The base of the shoe feels oddly narrow. I, like just about every runner, tend to pronate ever so slightly, so having a shoe that is a little more hourglass-shaped or at least has a wider platform under the ball of the foot gives me extra stability on smooth or technical terrain.

I realize that having just exploded my ankle might have my headspace a little more focused on stability than normal, but even when I wore this shoe hiking, I noticed I was a little uneasy walking down technical sections because it felt like I would roll to the outside. It’s not a huge deal breaker, but for a race shoe, I’d want a shoe that doesn’t slow me down at all, and needing to be extra cautious because of stability might negate all the hard work On did to get this shoe so light and race ready.

Adding on to that, I felt like the outside of my foot was a little cramped, but I had plenty of room on the inside, near my big toe. I think just fixing the shape of the toebox in general might be needed in this shoe. I’d be curious to see the state of my feet after several hours, knowing that it’s a little snug now. Conversely, I did wish my heel locked down a little better. I do wear inserts in my shoes, which always push my heels up ever so slightly, but I typically don’t have issues with my heels coming out. I had to use the last lace eyelet to ensure my heel was locked in.

I realize that having just exploded my ankle might have my headspace a little more focused on stability than normal, but even when I wore this shoe hiking, I noticed I was a little uneasy walking down technical sections because it felt like I would roll to the outside. It’s not a huge deal breaker, but for a race shoe, I’d want a shoe that doesn’t slow me down at all, and needing to be extra cautious because of stability might negate all the hard work On did to get this shoe so light and race ready.

Adding on to that, I felt like the outside of my foot was a little cramped, but I had plenty of room on the inside, near my big toe. I think just fixing the shape of the toebox in general might be needed in this shoe. I’d be curious to see the state of my feet after several hours, knowing that it’s a little snug now. Conversely, I did wish my heel locked down a little better. I do wear inserts in my shoes, which always push my heels up ever so slightly, but I typically don’t have issues with my heels coming out. I had to use the last lace eyelet to ensure my heel was locked in.

MICHAEL: While I generally enjoyed the race-oriented, lightweight construction of the Cloudultra Pro, it did leave something to be desired as far as fit in the forefoot goes. Like Reese, I experienced some instability there, and while it was minor, it was enough for me to continue to recommend the slightly wider, plateless Prodigio Pro over the Cloudultra Pro for the most technical of race courses with ultra-steep descents. So with that caveat aside, the Cloudultra Pro ate up everything else, with the exception of that snake who actually tried to eat me instead.

Final thoughts on the On Cloudultra Pro

TAYLOR: Man, it has taken me a long time to get here. All this is to say, the On Cloudultra Pro felt glorious on the trails. While each component of the On Cloudultra Pro is of premium quality, their sum makes the Cloudultra Pro work so proficiently.

On put on a masterclass in creating an ultra-distance shoe that can go just about anywhere and at any pace. I love that they shed some of the roadie expectations of what a racer should feel like and took their time on solving for efficiency. That doesn’t mean it rejects race day vibes at all.

Overall, the underfoot performance left little to be desired, especially when going the distance. It was a beautiful combination of cushion, stability, and liveliness. It wasn’t too aggressive, nor did it lack. When all was said and done, this recipe performed in a manner that made the multi-year wait worth it.

REESE: This shoe feels like it falls somewhere between TNF’s Summit Series Vectiv Pro and Vectic Sky. It’s like they took a max-cushioned shoe and slimmed it down, but they didn’t make it so minimal that it wouldn’t be 100-mile ready. They made it super light and designed a rocker that doesn’t stress out your ankle and brain on technical terrain. They even embraced a little crossover in the color department.

No shoe has knocked off the Vectic Sky from its rightful spot as my favorite race shoe in years- it’s one of the few shoes I routinely buy in bulk. Maybe it’s my busted ankle or the slightly too big fit holding it back from grabbing it on all my runs, but this shoe is so close to being my next favorite shoe. I think it needs a little bit of work on the toe box fit and the width of the shoe, and it could be one of the best shoes on the trail market. That’s a bold prediction. Hey, On designers, if you’re reading this, please don’t let me down.

MICHAEL: Like my Dirt Division compatriots, I found the Cloudultra Pro an exceedingly fun and fast shoe for the abbreviated test period I had it for. I really look forward to hopefully racing in it this year, which brings me to one last thought. We’ve talked about why this shoe is great, but I should mention who exactly this shoe is great for.

I think the Cloudultra Pro could handle just about anything from 50k to 100M without a hitch. It’s lightweight, and the slightly more plush midsole durometer will really help save those feet over the longer distances in that range. As far as technical ability goes, I found that this shoe could handle just about everything, so long as it wasn’t ultra steep or rocky. If your course falls somewhere in there, you’ll no doubt find something to love about On’s latest flagship racer.

Readers are likely tiring at this point, hearing me go on and on about the Prodigio Pro and how much I enjoy it, but it really is a great shoe, and there’s no denying that every race day super shoe to be released after it this year will have to go through the unfortunate comparison. Since reviewing the Prodigio Pro, the Cloudultra Pro is the first to get really close, and puts forth an alternative, yet highly convincing argument in the battle for trail super-shoe supremacy, and looking absolutely beautiful doesn’t hurt that argument one bit.

You can pick up the On Cloudultra Pro for $260 from Running Warehouse (featuring free shipping and 90-day returns) by using the buttons below.