The RW Takeaway: Designed to better support runners of all sizes, the Cloudstratus delivers plenty of stable and responsive cushioning for runs of any distance.
- Stiff midsole feels sturdy yet energetic for both short- and long-distance efforts
- Softer ride than first generation Cloudstratus, but still a firm shoe
- High-volume toebox and soft, slightly stretchy mesh upper accommodate wide feet
Weight: 10.7 oz (M), 9.5 oz (W)
Drop: 8 mm
On’s “CloudTec” midsole cushioning consistently surprises runners who expect the company’s familiar running-on-clouds sensation. The unique hollow pods are made from Helion, a blend of EVA and OBC (Olefin Block Copolymer)—essentially, it’s a mix of one stiff material and one soft material in a single compound. Though the midsole provides ample cushioning, it’s not the super plush and bouncy feeling you’d imagine underfoot while sailing through big, fluffy cotton-candy skies. Even with a double layer of the pods underfoot, the Cloudstratus best serves runners who dig a firm ride for long runs. It’s also a great option for heavier runners who feel under-supported by softer, squishy midsoles.
Swiss Midsole Tech
Since the Cloudstratus is no featherweight, On uses both a rockered midsole and a customized thermoplastic plate, called a Speedboard, to smooth and quicken transitions. Many of On’s shoes incorporate these Speedboards, but they’re not all built the same. By injecting it with liquid, On can tune the board’s thickness, arc, flexibility, and torsion to each shoe’s specific use. For example, trail models like the Cloudventure are more pliable so the midsole can more readily twist and adapt over rocks and uneven terrain. Comparatively, the Cloudstratus’s Speedboard has a wider midsection that feels noticeably stiffer and resists excessive inward pronation.
How We Tested
Longtime RW readers likely know our extensive testing process by now. But if you’re new to our shoe reviews (welcome!), here’s the quick and dirty on how we evaluated the Cloudstratus. Swiss shoe brand On provided us with sample pairs in a range of sizes; eight of those pairs went on the feet of runners from our Wear-Test Team, while a men’s size 9 and a women’s size 7 were sent to our RW Shoe Lab for mechanical tests to measure flexibility, cushioning, stiffness, and energy return. Our Wear-Test Team includes more than 250 runners of all ages, sizes, and speeds from across the US who we ask to put at least 100 miles on their test shoes in 30 days.
We distributed pairs of the Cloudstratus among runners of various experience levels, body types, and ages. The test pool for this specific shoe included: a 51-year-old, 50-miles-per-week-logging underpronator; runners in larger bodies training for half and full marathons; and a midfoot-striking schoolteacher who stands just over five feet tall. We’ve taken into account all our testers’ experiences for this review.
Holes in the Midsole? There’s a Reason.
Turns out, Swiss cheese and Swiss midsoles do have something in common. But those holes in On’s foam pods have a larger benefit. The open pockets allow the midsole to lightly compress and disperse the impact of each footstrike, while preventing the cushioning from “packing out” and losing its supportiveness. Testers reported that the result was a peppy toe-off, delivering support without slowing down turnover. “I liked the responsiveness and rebound of this shoe,” one said. “Though I definitely felt the stiffness underfoot, this shoe did a good job of returning energy and didn’t feel sluggish.” However, a few testers of smaller stature noted that the shoe felt too unwieldy and firm.
Soft, Airy, and Spacious Upper
On’s star-lacing extends farther down toward the toe in a crisscross pattern. (This helps recruit more of the upper’s polyester mesh for a secure fit when you pull the laces taut.) Some testers said the design took awhile to get used to; others immediately liked the asymmetrical style, finding that it worked well with the shoe’s inner sock to wrap across the forefoot and really hug the instep. “The upper is lightweight, breathable, and quick-drying and the toebox feels nice and wide without being sloppy,” one tester said. “The laces snugged up the midfoot nicely to prevent any slippage.”
In the past, several testers had issues with On’s angular ankle collar. Some cited difficulties in getting a secure fit, while others experienced rubbing or blisters. None of our testers reported trouble in that area with this shoe, which is likely due in part to restructuring of the Cloudstratus’s heel. On deepened the heel cup for this newer version, so the foot sits more comfortably and shifts less in the rear of the shoe.
Words from One Wear-Tester
Jennifer W. | Tester since 2020
Arch: Flat | Gait: Neutral | Footstrike: Midfoot
Favorite Shoe: Saucony Guide
“The hollow openings in the Cloudstratus’s midsole concerned me at first, but this funky cushioning somehow captured and returned energy to my stride. There’s some kind of rebound-recoil magic-mojo going on, because the midsole itself is not ‘plush’ by any stretch. While running, I felt a rebound-like effect that made my stride feel more energetic and effortless. Since most of my miles are on pavement, the impact adds up. Despite feeling less softly cushioned, they somehow reduce the impact on my joints. The first time I ran in the Cloudstratus, I did a couple of miles and felt so good that I turned around and went back out for a couple more. The shoes were very solid and stable, and had just the right amount of arch support for my flatter feet. I don’t know that I’ve ever been ‘in love’ with a running shoe before, but I’ve gushed so much about how wonderful these shoes are for me. I think we’re getting pretty serious! I’m looking forward to wearing them as I add longer runs to my marathon training schedule.”