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Amid a sea of carbon-plated racing shoes hitting the dirt, new On Cloudultra Pro is a true trail racing maverick.
It’s a maximally cushioned shoe with an extremely responsive midsole foam, but believe it or not, it bucks the trend of top-tier trail racing shoes with carbon-fiber plates embedded in the midsole, and quite frankly, that’s one of the reasons this one is great.
Over the past two years, there has been the emergence of a new breed of trail racing supershoes. The Adidas Terrex Agravic Speed Ultra ($220), Nike Ultrafly ($270), Hoka Tecton X 3 ($275) all have carbon-fiber rods or plates aimed at providing a combination propulsion, protection, and stability, as do forthcoming Hoka Rocket X Trail (September 1), and Ultrafly 2 (January 2026), but the On Cloudultra Pro ($260) and NNormal Kierag 2 ($195) do not.
Through extensive testing in a lab and on the trails, On footwear engineers determined that a rigid carbon-fiber plate wasn’t conducive for long-haul efficiency on the trails the way similar shoes do on the roads. Instead, the On Cloudultra Pro has a responsive and flexible plastic plate, which contributes to a flexible and energetic sensation but also a very stable ride. Ultimately, it’s a trail shoe that’s capable of running fast on a lot of surfaces.
The shoe hit running stores two weeks ago and was on the feet of Montana trail runner Jeff Mogavero during his breakthrough fourth-place effort at the June 28 Western States 100. It was an ideal shoe for that course because it has a mix of moderately technical trails, smooth dirt trails, gravel roads, and a few sections of paved roads—not to mention 90+ degree heat most of the day. It could have the right mix for you, too, if you’re planning to run a trail marathon or an ultra-distance race this summer.
What’s New: This is a brand new shoe engineered for optimal energy return, cushioning and stability. It’s built on a dual-layer Helion HF hyperfoam midsole with a softer layer of foam on top of the embedded plastic Speedboard and a firmer layer of foam below it. Just as important are the array of the grippy, 3.5mm directional outsole lugs, the durable leno weave technical mesh upper, and integrated tongue that creates a secure, sock-like fit.
Fit/Feel/Ride: The Cloudultra Pro fits true to size with a medium-volume interior and plenty of wiggle room in the toe box. (It’s probably not roomy enough for removing the sockliner and inserting an after-market footbed.) The step-in feel is soft, compact, and snug, thanks to the wide, lightly padded tongue that is secured with a wide stretchy gusset. It has a high heel collar with medium padding that helped keep my foot in place on all sorts of terrain.
While I found the fit of this shoe to be exceptional, I really loved the ride. It feels like a light and responsive well-cushioned road shoe, only with a low-profile grippy trail tread. The plastic Speedboard embedded in the midsole gives off a soft, but semi-stiff sensation that offers a good amount of propulsion and underfoot protection without any sharp, ankle-rolling movements. It handles smooth dirt trails with aplomb, but it’s also sufficient and smooth on moderately technical terrain (bigger rocks, roots, mud, pebbles, gravel, trail debris, etc.) because there’s some degree of flexibility and it’s very stable.
Price: $260
Weights: 9.1 oz (women’s 8); 10.5 oz. (men’s 9)
Heel-Toe Offset: 6mm; 39mm (heel), 33mm (forefoot)
Why It’s Great: It’s great because it’s very runnable on most types of terrain, and I found it to be especially good on runs that combine dirt, rocks, grassy fields, and gravel, as well as paved roads and concrete bike paths. It’s not as fast and electric as a pair of road running supershoes, but that’s OK. The key is that it does offer a good amount of propulsion, but it doesn’t sacrifice speed or stability on any of those surfaces.
Why You’ll Love It: The On Cloudultra Pro has ample heel cushioning under the heel and arch, but it also provides a good amount of feel for the trail in the forefoot. It’s not a hyper-nimble shoe that I’d choose to take on extremely technical or craggy routes, but it is agile enough for running fast (or slow) on most types of terrain. I have run all sorts of trails and distances in it so far, and each time I enjoy it more.
I did a two-hour long run in these shoes on singletrack trails in the Granite Chief Wilderness high above Palisades Tahoe ski area, ran an out-and-back run on the semi-technical final 5-mile section of the Western States Trail, and I have run several mild to moderate trails in the foothills of Boulder, Colorado. The bottom line is that it’s one of my favorite trail shoes of the year so far—along with the Norda 005—because it can do most things very well but also because it’s capable of quick-cadence running.
Why You Might Not Love It: If you prefer low-to-the-ground feel for the trail, the On Cloudultra Pro might not be to your liking. The midsole is thick and soft upon impact, so it tends to mute the proprioceptive connection to the ground a little bit. The shallow outsole lugs are a trend of trail racing shoes, but it makes this shoe a little vulnerable on technical terrain and wet, sloppy trails. (It will benefit nimble runners who are precise with their footsteps, but not so much for runners who lack agility or balance out on the trails.)
Pro: The pliable upper is lightweight, quick-drying, and breathable, but also very durable. The toe bumper is only lightly reinforced, but for such a light and fast shoe it offers decent protection. Thanks perhaps to the plastic plate embedded in the thick foam, I didn’t have any complaints with lateral or medial abrasions or sharp “stingers” poking my feet through the bottom of the shoe.
Con: Like any pair of supershoes, the high-end midsole foam chassis of the On Cloudultra Pro probably isn’t going to be as durable as more traditional, longer-lasting foams in everyday trail running shoes, and I sense that’s the case with this one even though I still expect to get at least 300 miles out of it. Plus, the price is very steep (especially for a shoe without a carbon plate), but that’s also the way high-end supershoes are trending.
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Senior editor Brian Metzler has wear-tested more than 2,500 running shoes and is the author of “Kicksology: The Hype, Science, Culture and Cool of Running Shoes” (2019) and “Trail Running Illustrated” (2019). He has raced just about every distance from 100 meters to 100 miles, but he’s most eager to share stories about his experiences pack burro racing in Colorado.