Our verdict

The On Cloudrunner 2 Waterproof is a strong pick for runners needing a winter-ready, weather-resistant shoe, but it’s not ideal for everyone. In our tests, we found the firm midsole and heavy design may not suit those preferring lighter, softer shoes. However, we were impressed by its premium build, reliable traction, and excellent stability, making it a fantastic option for harsh weather running and walking.

Pros

  • Well cushioned
  • Amazing reflective elements for safety
  • Reinforced waterproof upper
  • Fantastic stability
  • Excellent for cold, wet winters
  • Build quality
  • Doubles as a walking shoe
  • Reliable grip

Cons

  • Unnecessarily heavy
  • Heel durability issues
  • Priced higher than competitors
  • Firm midsole

Audience verdict

76
Bad!

Who should buy

We tested the On Cloudrunner 2 Waterproof extensively and believe it’s an excellent choice for:

  • Runners who loved the On Cloudrunner 2 but need a winter-ready version for freezing temperatures and wet, unpredictable conditions.
  • Those seeking a mild-stability trainer with a somewhat firm ride that's perfect for cold climates. 
  • Anyone needing a versatile, weather-resistant shoe for running or walking with reliable grip and all-day comfort.

On Cloudrunner 2 Waterproof

Who should NOT buy

We found that the On Cloudrunner 2 Waterproof is heavy; there's simply no way to sugarcoat it. For runners who prioritize lighter shoes, there are much better choices available. Both the Hoka Clifton 9 GTX (for road running) and the Hoka Challenger 7 GTX (for mixed terrain) offer similar versatility while remaining much lighter on your feet.

In our view, the firmer midsole of the Cloudrunner 2 Waterproof also could be an issue. For those seeking a softer ride, the Nike Pegasus 41 GTX stands out. It combines waterproof protection with a ReactX midsole, all at a slightly lower price point than the On.

On Cloudrunner 2 Waterproof parts

Cushioning

Heel stack

The Cloudrunner 2 Waterproof is a dependable daily trainer, and its 35.8 mm heel stack reflects that perfectly. We believe this height strikes a balanced mix of soft cushioning and everyday practicality, excelling for long runs, casual walks, or even long workdays.

CloudTec at work!

For runners seeking more stack height, On offers the Cloudmonster 2, which features a few extra millimeters in this area. However, there’s no waterproof edition of the Cloudmonster 2 currently available, and the difference in height is barely noticeable.

On Cloudrunner 2 Waterproof Heel stack
Test results
Cloudrunner 2 Waterproof 35.8 mm
Average 33.9 mm
Compared to 365 running shoes
Number of shoes
22.5 mm
Heel stack
46.3 mm

Forefoot stack

Our next measurement focused on the forefoot, which we also found comfortably placed in the well-cushioned category at 27.5 mm. For a daily trainer, this strikes a smart balance, avoiding the overly bulky feel of maximalist designs that could hinder everyday use.

On Cloudrunner 2 Waterproof Forefoot stack
Test results
Cloudrunner 2 Waterproof 27.5 mm
Average 25.3 mm
Compared to 365 running shoes
Number of shoes
13.7 mm
Forefoot stack
37.1 mm

Drop

We found that while On states this shoe has a 10-mm drop—placing it on the higher end of the spectrum—our measurement revealed 8.3 mm.

This difference delivers a nearly identical feel to a 10-mm offset and keeps the shoe versatile for all footstrikes. Unlike many On models that lean towards a lower drop, this design strikes a balanced profile suitable for everyone.

On Cloudrunner 2 Waterproof Drop
Test results
Cloudrunner 2 Waterproof 8.3 mm
Average 8.6 mm
Compared to 365 running shoes
Number of shoes
0.0 mm
Drop
16.1 mm

Midsole softness

Note: a low durometer measurement equals a soft material, whereas a high measurement means it's firm.

There seems to be a common perception—perhaps due to the CloudTec system—that On running shoes are super plush. In our experience, however, this couldn’t be further from reality, as every On shoe we've tested leans towards a firmer ride, especially when compared to cushioned daily trainers like the New Balance Fresh Foam X 1080 v13 or the ASICS Nimbus 26.

That said, the distinctive "clouds" partially soften the firm Helion foam by collapsing on every stride. Still, the Cloudrunner 2 Waterproof maintains a notably firm underfoot feel—ideal for runners who prefer firmer foams over pillow-like midsoles.

On Cloudrunner 2 Waterproof Helion

And we want to emphasize an essential point about running shoe foams: softer doesn’t mean more cushioned. In fact, firmer midsoles hold their structure better, providing more consistent and reliable cushioning even if they feel less soft.

On Cloudrunner 2 Waterproof Midsole softness
Test results
Cloudrunner 2 Waterproof 28.1 HA
Average 21.1 HA
We use an average of four tests. The photo shows one of those tests.
Compared to 292 running shoes
Number of shoes
8.5 HA
Midsole softness (soft to firm)
38.9 HA

Midsole softness in cold (%)

As a firm running shoe, performing well in cold temperatures was crucial to avoid becoming excessively rigid during winter—the primary use case for the Waterproof edition.

Fortunately, it only became 22.1% firmer, a favorable result. This performance stems from Helion foam’s composition, blending EVA with Olefin Copolymers for enhanced weather resistance.

On Cloudrunner 2 Waterproof Midsole softness in cold (%)
Test results
Cloudrunner 2 Waterproof 22%
Average 26%
Compared to 292 running shoes
Number of shoes
0%
Midsole softness in cold
100%

Insole thickness

The EVA insole measures an average 4.2 mm in thickness, so let’s proceed to the next test.

On Cloudrunner 2 Waterproof Insole thickness
Test results
Cloudrunner 2 Waterproof 4.2 mm
Average 4.5 mm
Compared to 361 running shoes
Number of shoes
1.5 mm
Insole thickness
7.3 mm

Rocker

In our view, the moderate stack height and versatility of this model didn’t call for a dramatic rocker shape at all.

On Cloudrunner 2 Waterproof lateral

We believe On reached a similar conclusion, as the Cloudrunner 2 Waterproof features a classic design in both heel and forefoot, with a very subtle curvature.

On Cloudrunner 2 Waterproof Rocker

Size and fit

Size

On Cloudrunner 2 Waterproof is slightly small (13 votes).

Owners of this shoe, how does this shoe fit?

1 size small ½ size small True to size ½ size large 1 size large
Compared to 302 running shoes
Number of shoes
½ size small
Slightly small
True to size
Slightly large
½ size large

Toebox width - widest part

Despite the thicker upper due to the waterproof membrane, we still found the vertical room ample, making the Cloudrunner 2 Waterproof great for individuals with higher-volume feet.

Afterwards, we used our digital caliper to measure the toebox's widest part, recording a spacious 100.3 mm.

On Cloudrunner 2 Waterproof Toebox width - widest part
Test results
Cloudrunner 2 Waterproof 100.3 mm
Average 98.5 mm
Compared to 366 running shoes
Number of shoes
91.6 mm
Toebox width - widest part
104.9 mm

Toebox width - big toe

We discovered that the big toe area features a standard taper while still providing good space, measuring 78.6 mm.

On Cloudrunner 2 Waterproof
That loop is definitely not necessary and adds weight to an already hefty shoe.

Although not an Altra-style design by any means, we believe it's rounded enough to deliver a good fit for most runners with ease.

On Cloudrunner 2 Waterproof Toebox width - big toe
Test results
Cloudrunner 2 Waterproof 78.6 mm
Average 78.4 mm
Compared to 240 running shoes
Number of shoes
67.6 mm
Toebox width - big toe
89.2 mm

Stability

Lateral stability test

We believe that the Cloudrunner 2 Waterproof fits nicely into the mild stability category, comparable to models like the ASICS GT 2000 13 or Hoka Arahi 7. It strikes an interesting balance—wider and stiffer than a daily trainer but less bulky and restrictive than a traditional stability shoe.

Torsional rigidity

One of the most prominent updates in the On Cloudrunner 2 Waterproof is its increased stiffness. In our lab, we measured a 5/5 score—up from 3/5 in the non-waterproof version—making it less ideal for those sensitive to stiffer shoes, but giving a notable stability boost.

Test results
Cloudrunner 2 Waterproof 5
Average 3.3
Compared to 344 running shoes
Number of shoes
1
Torsional rigidity
5

Heel counter stiffness

The heel counter is exceptionally stiff—so rigid that we could barely move it—placing it much closer to a stability shoe than a typical daily trainer. While heel strikers seeking added support might appreciate this design, runners with sensitive heels or Haglund’s deformity may find it uncomfortable.

Test results
Cloudrunner 2 Waterproof 5
Average 2.9
Compared to 328 running shoes
Number of shoes
1
Heel counter stiffness
5

Midsole width - forefoot

After completing our manual assessments, we measured the midsole width using digital calipers, starting with the forefoot. At 119.0 mm, it falls on the wider end of the spectrum, contributing significantly to the shoe’s remarkably stable feel.

On Cloudrunner 2 Waterproof Midsole width - forefoot
Test results
Cloudrunner 2 Waterproof 119.0 mm
Average 114.0 mm
Compared to 366 running shoes
Number of shoes
103.3 mm
Midsole width - forefoot
126.9 mm

Midsole width - heel

On is known for designing running shoes with narrow heels, such as the Cloudmonster Hyper, but its stability-oriented models like this one break from this trend. Measuring 96.2 mm, this heel width makes it a great option for rearfoot strikers seeking support while keeping their feet warm and dry.

On Cloudrunner 2 Waterproof Midsole width - heel
Test results
Cloudrunner 2 Waterproof 96.2 mm
Average 90.7 mm
Compared to 366 running shoes
Number of shoes
73.0 mm
Midsole width - heel
106.6 mm

Flexibility / Stiffness

The waterproof upper introduces additional material, resulting in reduced flexibility. To measure this, we conducted our standard 90-degree bend test and recorded 26.3N.

While still flexible and suitable for daily wear, it’s noticeably stiffer than the 21.1N of the non-waterproof version.

Test results
Cloudrunner 2 Waterproof 26.3N
Average 28.2N
We use an average of four tests. The video shows one of those tests.
Compared to 348 running shoes
Number of shoes
2.2N
Flexibility <> Stiffness
72.1N

Weight

The most noticeable drawback of the On Cloudrunner 2 Waterproof is its added heft. At 11.4 oz (323g), it’s significantly heavier than the regular On Cloudrunner 2, which weighs just 9.7 oz (275g).

In our view, while it’s understood that waterproof membranes add weight, other Gore-Tex-equipped shoes manage to remain lighter. We tested several comparable models that didn’t tip the scales like this one, reinforcing our belief that weight is the shoe's weakest aspect.

On Cloudrunner 2 Waterproof Weight
Test results
Cloudrunner 2 Waterproof 11.39 oz (323g)
Average 9.38 oz (266g)
Compared to 366 running shoes
Number of shoes
5.61 oz (159g)
Weight
12.59 oz (357g)

Breathability

After testing hundreds of running shoes we’ve learned that claims of breathability in Gore-Tex shoes often don’t hold up. But let’s just dive in and see what happens.

We began with our smoke test, and the result is crystal clear. This shoe, undoubtedly, ranks among the least breathable models we’ve tested in the lab. The lack of airflow earned it a firm 1 out of 5 score. Rest assured, the machine’s settings were identical to when we tested the Supernova Prima.

Next, we examined the upper of the shoe we cut in half using our light test. The outcome was as expected—no light passed through the dense fabric. This result strongly indicates restricted ventilation, confirming what we already suspected. And for further verification, we turned to our microscope.

On Cloudrunner 2 Waterproof microscope 1

It revealed an ultra-tight, Gore-Tex-like fabric engineered to repel water effectively. However, this impermeable barrier also prevents air and moisture from escaping, trapping heat and reducing comfort when running in hot temperatures.

On Cloudrunner 2 Waterproof microscope 2
On developed its own waterproof upper instead of relying on Gore-Tex.

Despite its ventilation shortcomings, we found the upper to be impressively padded and high-quality. Its 100% recycled materials reflect also a commitment to sustainability, which we genuinely appreciate!

All in all, this upper offers robust protection for harsh weather, but it’s clear that breathability is not part of the equation.

Test results
Cloudrunner 2 Waterproof 1
Average 3.8
Compared to 295 running shoes
Number of shoes
1
Breathability
5

Durability

Toebox durability

On asks for a premium on this shoe compared to other daily workhorses, and with that may come an expectation of enhanced durability. In our experience, runners paying more often anticipate a longer-lasting, well-built option.

Our first test focused on the toebox, which we found to perform quite well. After testing, we discovered a solid 3/5 score—a promising start.

On Cloudrunner 2 Waterproof Toebox durability
Test results
Cloudrunner 2 Waterproof 3
Average 2.5
Compared to 229 running shoes
Number of shoes
1
Toebox durability
5

Heel padding durability

The heel quickly disappointed us as soon as the Dremel made contact with the lining.

That's a 1/5 score in durability, period. In our view, this is a significant concern for runners prone to heel wear.

On Cloudrunner 2 Waterproof Heel padding durability
Test results
Cloudrunner 2 Waterproof 1
Average 3.2
Compared to 225 running shoes
Number of shoes
1
Heel padding durability
5

Outsole hardness

Brands often tweak outsoles for Gore-Tex shoes to optimize wet-surface performance, but On retained the same rubber and pattern from the Cloudrunner 2. In our tests, the outsole clocked 84.5 HC on the Shore C durometer.

On Cloudrunner 2 Waterproof

Is this the right choice? In our view, it depends on your usage. For runners using this shoe year-round—particularly on dry surfaces—it’s a fantastic option.

However, for those in consistently wet environments, the grip and water evacuation may feel slightly underwhelming, though we found the rubber performs decently in those conditions.

On Cloudrunner 2 Waterproof Outsole hardness
Test results
Cloudrunner 2 Waterproof 84.5 HC
Average 80.1 HC
We use an average of four tests. The photo shows one of those tests.
Compared to 346 running shoes
Number of shoes
60.3 HC
Outsole hardness
93.0 HC

Outsole durability

On usually delivers in outsole durability, and the Cloudrunner 2 Waterproof proved no different. After testing with our Dremel, we found only a 0.8 mm dent—a solid result that reinforces the brand’s reputation.

In our view, the durability could be near-limitless when used predominantly on wet surfaces, where reduced abrasion minimizes wear.

On Cloudrunner 2 Waterproof Outsole durability
Test results
Cloudrunner 2 Waterproof 0.8 mm
Average 1.0 mm
Compared to 207 running shoes
Number of shoes
0.0 mm
Outsole wear
2.0 mm

Outsole thickness

We also measured 3.0 mm of outsole thickness, providing an ample amount of rubber to support its good durability.

On Cloudrunner 2 Waterproof Outsole thickness
Test results
Cloudrunner 2 Waterproof 3.0 mm
Average 3.2 mm
Compared to 365 running shoes
Number of shoes
1.0 mm
Outsole thickness
6.0 mm

Misc

Price

On has never been known for offering bargain-priced shoes, and this model is no different. True to the Swiss brand's reputation, you’ll pay a slight premium—but in return, you get exceptional build quality. Whether it’s worth it depends entirely on your priorities.

Test results
Cloudrunner 2 Waterproof $170
Average $145
Compared to 366 running shoes
Number of shoes
$60
Price
$285

Reflective elements

The On Cloudrunner 2 Waterproof elevates its already impressive visibility with the addition of a new reflective detail, while retaining the glowing logos from the regular edition that we absolutely loved.

Test results
Cloudrunner 2 Waterproof Yes

Tongue padding

The tongue padding in this waterproof upper is slightly thinner than its regular counterpart, still measuring a comfortable 8.0 mm. In our view, it still provides a plush feel during runs despite the reduction.

On Cloudrunner 2 Waterproof

We also found that the Cloudrunner 2 Waterproof retains the extra eyelet for tying a runner’s knot. However, for a water-repellent shoe, we believe omitting this feature might better, as it prevents water from potentially seeping through the eyelet.

On Cloudrunner 2 Waterproof Tongue padding
Test results
Cloudrunner 2 Waterproof 8.0 mm
Average 5.8 mm
Compared to 363 running shoes
Number of shoes
0.5 mm
Tongue padding
14.2 mm

Tongue: gusset type

One notable update from the non-waterproof version is the reinforced tongue, now fully fixed to the sides to block water from getting into the upper. But of course, this change adds some extra weight.

On Cloudrunner 2 Waterproof Tongue: gusset type
Test results
Cloudrunner 2 Waterproof Both sides (full)

Heel tab

The heel mirrors the design of the regular Cloudrunner 2, which means it lacks a heel tab. This came as no surprise to us, given the consistent design choices in this model.

On Cloudrunner 2 Waterproof Heel tab
Test results
Cloudrunner 2 Waterproof None

Removable insole

The footbed of the Cloudrunner 2 Waterproof is removable and, aside from a slight heel flare, has nothing special. Therefore, feel free to replace it if needed.

On Cloudrunner 2 Waterproof Removable insole
Test results
Cloudrunner 2 Waterproof Yes