On Cloudboom Max: Boom or Bust?

Introduction to the On Cloudboom Max

KARL: When super shoes and super trainers made their way into the market several years ago, they were originally intended to be light and speedy; shoes that were meant to help you crush 26.2 miles to achieve your personal best. They originally came with the perception of being strictly for the elites — for fast and serious runners who will do whatever it takes to shave off a few seconds on their PB. 

Since then, shoe manufacturers have started to further break down the anatomy of the super shoe/super trainer and have figured out how to apply the same inherent characteristics to runners in a different bracket than the serious competitors. Being a part of the “Boom” franchise, which is the performance/race day line from On, the Cloudboom Max is positioned right below the Cloudboom Strike and was designed for the 4:00 hour and above marathoners. 

It’s a super shoe that prioritizes comfort features over blazing fast speed, with the goal of finishing a marathon comfortably. As a matter of fact, On officially describes the Cloudboom Max as a shoe to “Finish the Marathon” and the Cloudboom Strike for “PB-ing a Marathon.”

The On Cloudboom Max is “The Supershoe for the Everyday Runner”, but can this shoe do what it is intended for? Let’s take a closer look.

CHAD: Not to get all Dashboard Confessional on everyone, but “hands down” this was the shoe I was most excited for in 2025. When I heard rumblings from the BITR bigwigs after TRE that On was going to be releasing a super shoe designed for people racing a 4-hour to 5-hour marathon, I was stoked. I finally felt seen in an arena where those of us that are slower and/or bigger runners are often overlooked and left out in the cold. And I couldn’t think of a better brand to do it than On, a company that has been slowly but surely rising up in the ranks when it comes to the quality of their products.

When I got the shipping notification that FedEx would be delivering a product from On a few weeks back, knowing it was likely the Cloudboom Max, I was giddy like a school boy rizzing up a school girl. You could say I was turned “on.” For those of you who haven’t heard me mention it or read it in one of my recent reviews, I will be running the Chicago Marathon in October, shooting for a time between 4:00-4:30. In my head, I could be the perfect test case for whether the Cloudboom Max was in fact the best race day shoe for “slower” runners, and for me, a bigger runner. (I use quotations around “slower,” because speed and pace are all relative.)

The Cloudboom Max features dual density foams, both called Helion HF but the one immediately underfoot is PEBA and the one under the plate is TPEE. It also rocks the race day legal 40 mm / 32 mm (8 mm drop) stack and On’s Cloudtec midsole design.

What we like about the On Cloudboom Max

KARL: Starting with the upper, there are things to like and things to dislike. The fit is true to size with decent room in the toebox and a secure lock in the heel. The mesh is breathable and the gusseted tongue is sleek, thin, and race-like (makes sense). In my opinion, the best laces are sawtooth laces and they come standard out of the box, which is always great to see. The heel counter is nicely padded, but not by any extreme measure. The shoe is comfortable upon step-in and seeing as this is a shoe that prioritizes comfort, On seems to have succeeded in that department. 

There are also some slick branding details paired along with a massive “O” (or “Q”, for the uneducated commoners), on the lateral side — more on that in a bit, but the overall aesthetic may be hit-or-miss depending on how you feel about flaunting the premier Swiss brand as loud as possible.

The On Cloudboom Max comes equipped with dual density foams and a glass fiber plate. On the top layer right underneath your foot is Helion HF Pebax, reportedly the same found in the Cloudboom Strike, just tuned differently. In the middle sits an 8% glass fiber Speedboard, and on the bottom layer is the Helion HF TPEE, which is designed to provide stability and durability. On’s patented Cloudtec is also present though somewhat muted in comparison to the traditional cloud design, visibly mirroring its sibling, the Cloudboom Strike.  

It’s a little confusing to use “Helion HF” for both the foam names considering they’re both different materials, but I digress. The foams feel relatively soft but not squishy, with the Helion HF Pebax being well received all around. 

There is ample rubber coverage on the outsole – with the outer ends of the medial and lateral side covered while leaving the middle cross area exposed. I haven’t had any issues with traction on wet surfaces and any more coverage might be too much for a race day shoe, so again, I appreciate the balance here.

CHAD: I’m going to start with the aesthetics of this shoe, which are stunning. It definitely has the race day look of shoes like the Cloudboom Strike and the Cloudboom Echo 3, the shoes designed for faster runners to go fast. It most certainly has that Ricky Bobby, “I wanna go fast” look to it. The logo overlays and color usage (light pink and neon yellow with a mostly white upper) create a really fun design of the shoe. The upper has plenty of width and volume while gently hugging the foot for a race day fit.

The dual density foams (PEBA underfoot; TPEE under the plate) provide a comfortable feel upon initial step-in and walk-around. The ride while on the run is also stable, something which is always a plus when it comes to race day. There are very few race-ready shoes on the market that are stable-neutral, and I would add the Cloudboom Max to that category. Plus, something I always enjoy on super shoes is sawtooth laces, because the last thing you want to have to worry about is shoes coming untied and losing time.

What we don’t like about the On Cloudboom Max

KARL: Unfortunately, for me, the biggest problem with the On Cloudboom Max comes down to some bad rubbing in my left pinky toe. This left me with a blister in a spot I’ve never had an issue with before (in any shoe) and it wasn’t very pleasant.

On my first run, I felt this rubbing sensation but didn’t think much of it. I subsequently wore different socks of all thicknesses to try to help mitigate the problem, but it was something that always persisted in every one of my runs. The final straw for me was a 15 mile long run that I had to cut short to 10. By mile 7, I couldn’t wait to get these shoes off my feet. 

At first I thought it was caused by the giant “O” overlay on the lateral side I mentioned earlier, but to be honest, I’m still not quite sure what the issue is. Looking inside the shoe, there seems to be some fraying in the stitching where the tongue ends, which sits below the overlay and right where the upper and midsole meet. There doesn’t seem to be that same fraying on my right shoe, so it’s hard to pinpoint whether it’s just a manufacturing defect. I just know that I can’t run in this shoe without risking that sandpaper-ish burn.

But even ignoring that very personal issue, I’m just not super convinced the On Cloudboom Max would be the shoe I’d gravitate to for its expected purpose. In my size US M10.5, the shoe weighs in at 11.1 oz (315 g)  — which I consider to be on the heavier side for a trainer, but still fairly “OK” for the most part if it’s a max stack, protective cruiser like the Asics Gel-Nimbus 27 or Nike Vomero 18. 

But for a race day shoe, even if it’s meant for the “slower” pack, that weight is inconceivable to me for the full 26.2 (hell, even 13.1 is a hard sell). 

Although the ride itself isn’t terrible, there isn’t anything I feel to be special about it either. Going at a normal, easy pace for me, to some extent it feels smooth through the stride, albeit a bit stiff and blocky. But once the tempo starts to pick up, there isn’t any inherent rocker or “pop” off the forefoot. And while the softness of the PEBA foam is there and the slight flexibility of the nylon plate can be felt, all this tech just feels rather muted to me. And I’m left with a feeling that this is just a more premium version of a max cushion shoe like the Asics Gel-Nimbus, but with a plate. There’s still a lingering sensation of “boatiness” with the On Cloudboom Max, at least for my preference anyway.

I then started to think that maybe this shoe would benefit a bigger, heavier runner. We’ve seen throughout the last few years that shoes in this category tend to be favored by those who can really compress the foams and activate the plate (Adidas Adizero Prime Strung X 3 comes to mind). You’ll have to read Chad’s thoughts on that, but it just felt like I couldn’t really reap the benefits of whatever it is I’m supposed to get out of the Cloudboom Max.

CHAD:  To quote parents all around the world, “I’m not mad– I’m just disappointed.” First things first, this shoe ran short for me. I’ve worn a US M11.5 in every On shoe I’ve worn with no issue, including the recently released Cloudsurfer Max, and always had plenty of room in front of my toes. This was not the case with the Cloudboom Max. Let’s just say the toenails on my big toes are now a lovely shade of black and blue from being very crunched in the forefoot. Just something to consider, because it may not be universal, as I know Karl had no issues with length in his US M10.5. But this made for some very uncomfortable miles.

Remember that initial step-in comfort I referenced before? It went away fairly quickly on the run. You could feel the softness of the PEBA foam and stability of the TPEE foam; but those combined with the glass fiber plate made this shoe incredibly stiff and difficult to flex. It made for an overly blocky ride because the geometry of the shoe lacks any real rocker feel or toe spring to speak of. With the blocky feel and the insane stiffness, my feet and calves were so achy about 10 miles into my 15 mile run in them. I could understand this level of discomfort if I wasn’t used to running in plated shoes, but I do so every week for tempo runs and speed work, with no issue.

Unfortunately, I’m not done. I understand that this is a race day shoe designed more for comfort and less for speed. But it’s still race day, and I want to have something that feels light and energetic underfoot; this shoe is neither of those. I already hit on the blocky ride, but this shoe also tips the scales at 11.5 oz. for my US M11.5. That’s more than a lot of daily trainers on the market these days, and certainly heavier than other long run/marathon ready shoes I love in the super trainer category, like the Asics Superblast 2, which if I recall correctly comes in at around 10.5 oz. for my US M12, without a plate and even more foam underneath.

Final thoughts on the On Cloudboom Max

KARL: My personal best in the marathon is 3:25, so a shoe in this category may be a bit of a harder sell to me, but if I was going to pick a shoe with vaguely the same intention, my money would go straight to the Salomon S/LAB Spectur, a shoe that is marketed in the same category. Its lighter weight, the exciting pop in the ride, and all the comfort and protective features that this style of shoe boasts are present in the S/LAB Spectur (and it’s $5 cheaper).  

I know the pinky toe hot spot issue is probably just a “me” thing, and I would bet most of those who run in this shoe won’t have that same caveat. 

And, listen — I’ve come to accept the uptick in price that comes with On shoes. The company positions themselves as a premium market offering and the design of their product reflects a lot of that. But, for me, this is one of their models where I’m kind of left scratching my head. The On Cloudboom Max feels a bit too overbuilt and yields less-than-desirable results in the race department. We gave crap to the Hoka Cielo X1 for not being light enough for race day, and that’s almost 2 oz. lighter than the On Cloudboom Max! 

If I had to re-classify this shoe, I would tag it as a max stack super trainer to pair along with the Cloudboom Strike, because I personally wouldn’t want to wear this for race day. 

But, hey, that’s just me! Someone may find value in the $225 price tag for one shoe they can both train in and race in, since the goal is to just finish the marathon. In that regard, it makes sense. But it’s also hard to ignore all the offerings from other brands in the same tier. From the new Asics Megablast and Superblast 2, to the Glycerin Max or Hyperion Max 3 from Brooks, or even the Nike Zoom Fly 6 or Hoka Mach X 2 (X 3 coming soon) could be viable contenders in this category for midpack marathoners. 

Hopefully, the next iteration can slim down a bit more and maybe do a slight redesign on the upper/overlays as well as the geometry to make it a bit more aggressive on the toe-off. But until then, it’ll be interesting to see what else On does with the “Boom” franchise and if it gains any real traction in the race day category.

CHAD:  Well, I started this review by referencing Dashboard Confessional and now I’ll transition to Panic! At the Disco. I had such “high hopes” for the On Cloudboom Max. As a runner who pretty much perfectly fits the mould of who this shoe was designed for, I had every intention of doing whatever it would take to lace these up for Chicago in the fall. But after just a few runs in this shoe and more than 20 miles, I don’t know if I see myself wearing it again in any fashion. It’s not comfortable enough to be an easy run or recovery day shoe; it’s not light and snappy enough for tempo runs and speedwork; and it too stiff, heavy, and unwieldy to be a long run shoe. To be frank, for me it’s all panic and no disco.

I didn’t even mention the price of the Cloudboom Max, but I know Karl did. For $230 and under there are so many other options on the market for 4:00:00 – 4:30:00 marathoners that are going to be comfortable enough for the entire 26.2 mile course, like the Superblast 2, the Mizuno Neo Vista 2, the Brooks Glycerin Max, and others. They are not only more comfortable but also likely lighter, something which matters over the course of a 4+ hour marathon. I’m not sure what happened with the Cloudboom Max, because the idea itself is fantastic and there’s a few elements that appear geared towards the intended goal of a comfortable marathon racer for us “slower runners,” but this thing got away from them badly. And if you ask me, it’s a darn shame.

You can pick up the On Cloudboom Max for $230 on by using the buttons below.