Verdict from 11 experts and 5 user reviews

6 reasons to buy

  • Traction: Although not necessarily better than the Saucony Peregrine, the Cloudultra still "excels" on various terrains. Whether you're running on compact or loose gravel, tarmac, harder trails, rocky surfaces, or hard-frozen ground, the shoe has a good bite. 
  • Fit: It's perfectly snug for technical terrain. There were also no reports of heel slippage, especially on steep ascents and descents. 
  • Durability: After 80 km of running, experts have NOT seen any signs of wear and tear on the outsole. 
  • Protection: The combination of the shoe's high stack and firm Speedboard mutes sharp rocks and tree roots. Complementing this is the upper's sock-like wrap, preventing debris from getting into the shoe. 
  • Gusseted tongue: It creates better support and effectively locks the foot in place, lauded the reviewers. 
  • Looks: Almost everyone agrees that just like other On shoes, the Cloudultra "oozes" with oomph. They say it's just as great for everyday casual activities and can definitely be paired with some jeans or leggings. 

3 reasons not to buy

  • Firm ride: Because of the "questionable utilization" of the Speedboard, trail runners find the heel-to-toe transitions very rigid, thus requiring more effort. 
  • Narrow fit: Those with wide feet may suffer from the shoe's tight wrap. This has also been a concern among ultrarunners, stating that it can be uncomfortable, especially when the foot starts to swell.
  • Not for muddy and wet surfaces: The shoe's outsole only offers "little" traction on the said terrains. Moreover, chunks of mud can get trapped in the outsole, making the shoe "heavy and slippy." 

Bottom line

As a premium running shoe, the On Cloudultra is neither "disappointing nor inspiring." Touted as an ultra-running trail shoe, it is perfect for athletes who are looking for a versatile, endurance-focused model. Be warned, however, that the Cloudultra is a shoe that requires an "extensive" break-in period. 

Tip: see the best trail running shoes.

On Cloudultra: For the long and arduous runs 

As mentioned, the Cloudultra is primarily intended for ultra-distance running. To be truly effective when tackling long efforts on harsh, gnarly terrain, On made sure to include the following to generate protection and cushion:

  • There are two layers of Helion superfoam for a cushy underfoot feel and impact absorption. 
  • A Speedboard is also integrated into the midsole, which is intended for efficiency. But in the case of the Cloudultra, it's more like a rock plate than a speed-enhancing element. 
  • Addressing all concerns from past On running shoes, the Cloudultra no longer has channels (deep grooves) on its outsole. This is to prevent rocks and mud from getting stuck and for better multi-surface traction.

Unlike other On shoes: How premium is premium? 

The On Cloudultra is the first ultrarunning shoe from the brand that is centered on cushioning and comfort. The shoe borrows the Helion superfoam from the On's road shoes and employs the brand's new FlipRelease system, giving trail runners the option to loosen the shoe's fit as the feet expand after high-mileage efforts.

Lastly, the deep cuts on the outsole, which before, have caused some stone-trapping issues, is a thing of the past in this iteration. 

What is it for?

The On Cloudultra really shines in long-distance training on technical trails. As experts claim, its "largest strength" is apparent during ascents. When speeding down steep descents, athletes have found themselves cruising comfortably. 

Rankings

How On Cloudultra ranks compared to all other shoes
Top 10% trail running shoes
All trail running shoes
Top 16% On running shoes
All On running shoes
Top 9% neutral running shoes
All neutral running shoes

Popularity

The current trend of On Cloudultra.
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Author
Jens Jakob Andersen
Jens Jakob Andersen

Jens Jakob is a fan of short distances with a 5K PR at 15:58 minutes. Based on 35 million race results, he's among the fastest 0.2% runners. Jens Jakob previously owned a running store, when he was also a competitive runner. His work is regularly featured in The New York Times, Washington Post, BBC and the likes as well as peer-reviewed journals. Finally, he has been a guest on +30 podcasts on running.

jens@runrepeat.com