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On Cloudflow v3 Review: A Quietly Solid Lightweight Trainer
By Social Media Wizard Bach Pham

The 2021 On Cloudflow quietly returns with some major updates in the upper and underneath to help greatly refine the prior version. Considered their lightweight daily trainer, the On Cloudflow v3 features a streamlined design that can both do easy miles and longer distances for anyone looking for a traditional stack height shoe. The 2021 model features the brand's ongoing push towards sustainability with recycled materials in the upper on top of their signature Helion foam and CloudTec design.

Price: $139.95 at Running Warehouse
Weight: 8.5 oz, 238 g (men's size 8.5), 7 oz, 198 g  (women's size 7)
Stack Height: 30 mm heel, 24 mm forefoot
Drop: 6 mm
Classification: Lightweight Trainer


The new On Cloudflow features a revitalized upper design that slims down the padding from the prior version in favor of streamlined upper partially made with recycled materials (70% of the polyester is recycled materials). The outsole gets a critical customization that does away with one of the biggest complaints against On in the past: that it's "too firm." A new, softer rubber compound - also used in the Cloudboom Echo - helps clean up the underfoot experience and better highlight what the Cloudflow and Helion midsole can offer to runners.


The On Cloudflow v3 fits a quarter inch long. Most people should be able to go true to size and use the lacing to get a good lockdown without any issue. For those who are typically floating between sizes, I would recommend sizing down. For those who are fairly true to size 95% of the time, going true to size is fine unless you plan to use the shoe for aggressive workouts and would like a more snug fit. The upper compared to v2 is much more stripped down in the latest version, offering an average, but ample amount of space around the toebox. There is a wide version available. The heel is a bit loose on first slip-in, but the laces cinch down extremely well, allowing for a great lockdown. I did have to lace lock this pair, but have had zero issues with the fit since doing so. Going back to length, the upper slightly folds over the toes slightly on first run, but settles quickly and becomes a non-issue on ensuing runs once it molds to your feet. There is a moderate, support heel counter in the Cloudflow and a very minimal tongue that works just fine. I had no issues with breathability in both the cold and warm weather that this strange season has brought us in South Carolina (also low as freezing, as high as 80s!).

The insole is removable and there is a mild bit of arch support underfoot. I had tremendous problems with the overly aggressive arch support in v2, but they have done a good job taming that in the latest update. Overall, once I got dialed-in after the first run, I have had no issues with fit for the On Cloudflow v3.


With the same midsole underfoot, you would think the Cloudflow v3 would be a very similar shoe to its prior iteration. The On Cloudflow v3, however, a brand new rubber outsole that helps soften the harsher prior ride. the new rubber material (also seen in the Cloudboom Echo, their marathon racer) helps alter the underfoot dynamic of the shoe from firm to somewhere right in the middle of firm and soft. The best comparison is Goodyear rubber in both its grip and softness underfoot, allowing the midsole to shine. The Helion Cloudtec is still by no means the softest in the business, but feels on par with daily training foams like Adidas Lightstrike; something effective that gets the job done for daily mileage.

I would actually put the underfoot experience on par with the recent Adidas SL20.2 in terms of comfort and personally actually prefer the Cloudflow thanks to the Speedboard providing some rigidity throughout to make the shoe feel stable and guided. A mild rocker lets the shoe obtain a very natural stride. This makes the Cloudflow v3 feel versatile, allowing me to do easy paced runs or crank up the pace when I wanted. The Speedboard helps provide a little feedback when turning things up mid run. The shoe - while rigid in the heel - does have some decent forefoot flexibility despite the speedboard. It helps promote a bit of natural movement which is why it feels so reminiscent of the SL20.2.

Usage-wise, I found the Cloudflow good for both easy mileage and short-to-middle distance workouts. I took it out for long runs and enjoyed it (I have a preference for light, nimble footwear for long runs), but for those who prefer more cushioning underfoot may want to visit the Cloudstratus.

The durability of the new rubber seems to be holding up well so far after 50 miles. I have not seen any particular wear in the rubber compared to v2 where I did start seeing some dents around 40 miles. With the exposed foam and softer rubber outsole, I expect average durability for the Cloudflow v3, around 200-250 miles.

Finally, a long-time complaint of On shoes is rocks. I did get exactly two rock stuck in the crevice of the shoe during my 50 miles, but nothing that ever impeded my runs. This is not a shoe for trails by any means and I would recommend it for road use only.


This is a neutral shoe, but like all On-Running shoes there are several mechanics at play that helps make it more stable. The Speedboard goes throughout the full length of the shoe and does a nice job of providing rigidity, especially in the heel and midfoot. The guidance line underfoot helps promote some centering on the run while the moderately rigid heel counter provides a good locked-in fit. The shoe runs just slightly more towards firm and has a very moderate stack height by today's standard which all contributes to the Cloudflow feeling grounded. There is also the most minor of medial sidewalls which also works to help keep the foot dialed in.

The width of the shoe is relatively standard for a lightweight neutral trainer though, which makes it best labeled as a mild stable neutral shoe. The On Cloudstratus or Cloudswift provides a wider platform for those who want some geometry in their shoe, but a similar rolling ride seen in the Cloudflow.


Where On Sits in the Running Market Today
. When you look within the running community, it's hard not to notice that a lot of damage was done early on due to the combination of perceived firmness from On Running's models along with the the rock-catching underneath. It can be very hard for runners to drop their original perceptions of a brand, especially a newer one that is working to establish itself.

Where On managed to make huge growth however, has been through two unique avenues. The first is in the ultra and triathlete world. In many ways this makes perfect sense with founder Oliver Bernhard being a former World Champion in the duathalon. On has gone on to sponsor tremendous Ironman and Triathlon champions like Javier Gomez and Nicola Spirig. The Cloudflow reviewed today has long been a simple go-to in that department for many runners looking for a lightweight shoe that can pick up the pace. The underrated Cloudultra has also led many to impressive results this year for many of the brand's athletes on the trail.

Outside of running sports, On particularly took off in the lifestyle department with it's On Cloud model. Built to be a workout and crosstraining shoe, it became an iconic design that caught the attention of sneakerheads everywhere. In Germany, the Cloud's popularity soared so much it became the second most sold sneaker in the country behind the Nike Air Max. It's become fashionable among even celebrities like Will Smith and the Rock. The brand make it's biggest move in recent years with the signing of Roger Federer, who has helped build out a new tennis line and bring new attention to the new 10+ year old brand.

This leads to where On sits today as a brand when it comes to running. Between the lifestyle and steady advances in performance, On shoes have found a place for casual runners who want footwear that doubles for everyday use. The design happens to be stable and comfortable enough for walking, which adds to the value of the shoes for many fans of the company. From a performance standpoint though, the earlier struggles mentioned - a history of firmer than average footwear and a design that is susceptible to rocks - have been hard for On to escape. We have seen bigger gains in their trail running department with the solid On Cloudultra which has been a big winner for them in the ultra and Ironman world for several of their athletes. While On has moved in the right direction with their incremental changes, I'd really love to see them take a leap and make a big advancement in their midsole to help push them to the next level in their road running footwear, balancing modern comfort with their unique, stable design. Recently, the brand made their first nod in that direction with the introduction of their first super-stacked shoe in the On Cloudmonster.

"On's Future is Lifestyle, But it's Not Moving on From Performance"
"Roger Federer, Sneakerhead?"

Prior Generation Cloudflow
CULTURE CORNER: A Look into the History of On, and Understanding Swiss Design (using second generation On Cloudflow)

On Running was founded by Swiss athlete Oliver Bernhard, a three-time World Champion in Duathalon, and his partners Casper Coppetti and David Allemann (formerly CMO of Vitro, a Swedish furniture brand) in 2010. The goal of Bernhard and team was to create a shoe that had a cushioned landing, but firm takeoff. We have to remember that 2010 was the midst of two shoe paradigms: traditional running shoes with stability like the DS Trainer, Kayanos, and more, and the minimalist movement. The goal of On, while it sounds relatively common today with super shoes creating that soft platform and rigid takeoff, was not as commonly seen then.

On particularly took off in 2014 when two things happened with a brand new model that’s come to define the brand: the On Cloud. The original intention of the shoe was based on running (pun intended), and led to Swiss triathlete Nicola Spring’s silver medal in the Rio de Janeiro Olympics. The On Cloud also started to garner a cult status outside of running, with celebrities and sneaker fans taking appreciation of the sleek, modern design of the shoe. On has really embraced this, bringing a wide range of colorways to the Cloud model and continuing to evolve the shoe with both performance and aesthetic in mind. Since its running beginnings, the brand has involved in other areas, including hiking, lifestyle - embracing the On Cloud culture with new lifestyle specific entries - and most recently tennis in partnership with Roger Federer.
On has a couple of defining characteristics. There’s the cloudtec, those pods that are the basis for their entire line. The less discussed aspect of On that’s made them a worldwide success is the Swiss construction. While shoes have evolved and streamlined greatly in the past ten years, when you think about shoe models prior to 2010 you have a lot of big models like the Asics Kayano and Nimbus which embraced a construction or the absolute other end with things like the Vibram Five Fingers.  On, embracing its Swiss heritage, really brought to the table a stripped back design with its original On Cloud running shoe. Emerging out of the 1950s, Swiss graphic design schools emphasized a form following function, rather than over function mentality to their work. Their design is no surprise when it came to the Eastern European block of influence that was present in the country (Netherland’s De Stiji block geometry design, the squareness of Bauhaus architecture being two major influences). Over the years, “Swiss Engineering” and design only became more and more reformed, focusing on tight-knit, stripped back construction, solid colors and geometric patterns, and strong block writing that’s clear and efficient in delivering its messaging. This design nature is clearly seen in On’s running shoes. While there certainly is a simple, clean design aesthetic the shoe visually, upon closer examination you can see the functionality of the lines and colors to highlight the construction of the shoe. In this sea/petrol colorway, where the blue ends in the upper and the grey begins in the heel, you can feel the transition from the less structured forefoot area to the sturdy grey portion that protects the heel. The midsole coloration also signals a change going into the heel where a softer Helion midsole exists. The blue wrapping around the heel demonstrates where the heel padding ends and sturdy heel counter starts and ends. The upper design in general is shaved as far as it can go while still maintaining comfort, helping keep the weight down to as much as the material allows. The cloudtec even fall into the aesthetic, with the repeated square geometry throughout, cutting space where allowed while still maintaining symmetry. There isn't a part of the shoe that is overbuilt in anyway, which is a credit to On's construction. The Cloudflow is a good example of On taking Swiss engineering to the extreme to create a slick, dialed-in design from top to bottom. Sources Swedish Design: An Ethnography, Keith M. Murphy Modern Swedish Design: Three Founding Texts, edited by Uno Åhrén, Lucy Creagh, Mary Creagh, Helena Kåberg, Barbara Miller Lane, Kenneth Frampton What You Should Know About Swedish Design, aproposter On’s Future is Lifestyle, But It’s Not Moving From Performance, Highsnobiety Proper Interview: David Allemann Co-Founder of On, Proper


The Cloudflow runs a touch long in general for US sizing. Redialing the sizing not only would help with sizing decisions, but also with the minor folding over the toes I found in this model. In general I do think the upper is a nice refinement over the prior year, stripping things down yet still maintaining comfort throughout. While I find the underfoot ride comfortable to my needs, On will have to consider either a new foam or 2-3mm of additional stack to meet the demands of today's more cushion-oriented market. Added stack would also help promote more effectiveness in longer efforts up to the marathon for runners.


The On Cloudflow v3 is for someone looking for a cushioned ride that sits right in between firm and soft and features a more traditional height than today's growing market of high stacked shoes. The softer outsole opens up the Helion foam to showcase a protective, versatile ride. Similar to how we praise the Mizuno Waverider, the Cloudflow is a mild stable neutral thanks to its Speedboard, guidance line, and low stack height. Fans of shoes like the older Boston 8 or 9 and similar footwear will find similarities to the Cloudflow. It also just looks great and is comfortable for everyday activity and errands.

Rotation-wise, in-house at On this is an excellent pairing with the Cloudmonster, their maximal shoe. Using the Cloudflow for easy days and workouts and the Cloudmonster for recovery and slow, long efforts has been a really enjoyable. Any comfortable shoe you find for long distance training and recovery would be a great fit here. The Cloudflow also pairs well with a super shoe like the Puma Deviate Elite - which has a similar fit and shaping - which can handle long run duties and heavier workouts while the Cloudflow handles easy mileage and some occasional uptempo work like strides. For someone wanting to use the Cloudflow for most of their uptempo work and even racing, pairing a cushioned trainer like the Cloudmonster mentioned earlier would be great. The Cloudflow in general is a versatile option that can play into your shoe rotation in many ways.


Fit: B+ (Lengthwise, it may take trial and error to see which pair fits you best based on your sizing, but the shoe does a good job of locking the down the foot once you get the right size)
B+/A- (A good, mild rocker with a nice underfoot feel that's versatile for easy days to workouts. Longer efforts will depend on the runner's preference towards lower stack footwear)
Stability: B+ (Speedboard, rigid heel counter, minor sidewall, and guidance line all over stable mechanics for this neutral shoe. Width is average though. Look to Cloudstratus for a wider platform)
DPT/Footwear Science: B+ (Refinement from prior version through new outsole material and recycled upper offers a very sleek package from On that will draw newcomers)
Personal: A- (I have been able to dial in many different types of runs in the Cloudflow without complaint. A really nice mild stable neutral shoe)
Overall: B+/A- (An excellent upgrade over v2 and a shoe that could turn people to On for the first time)


Price: $139.95 at Running Warehouse.

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More from On Running
On Cloudstratus 2.0
- One of the best On shoes to date, especially for long distances
On Cloudswift 2.0 - A big update to their daily trainer, featuring sustainable materials
On Cloudboom - On's first attempt at carbon plated racing. Aggressive fun
On Cloudventure Peak - The brand's lightweight, nimble trail runner, with an extra sticky outsole
On Cloudflyer - On's light stability trainer
On Cloudace - On's heavyweight stability shoe

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Hoka Carbon X3  - A new ProflyX midsole and knit upper highlights this long distance racer's update
Hoka Mach Supersonic - A limited release Mach with Profly+ midsole
Brooks Hyperion Elite 2 - We dig back in time to take a look at Brook's current racing shoe.

Find all Shoe Reviews at Doctors of Running here.

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Bach Pham MS
Marketing and Social Media Manager
Master of Arts in Cultural Anthropology

Bach Pham is a 140 lb male with PRs of 23 5K, 52 10K. He typically runs between 25-35 miles per week at a variety of paces between 8:30 (tempo) -10:00 (recovery) min/miles. He typically prefers shoes that provide some mild to firm cushioning underfoot that is lightweight and responsive. Currently his goals are to complete the half and marathon distances.

Editor's Note: As always, the views presented on this website belong to myself or the selected few who contribute to these posts. This website should not and does not serve as a replacement for seeking medical care. If you are currently injured or concerned about an injury, please see your
local running physical therapist. If you are in the Los Angeles area, I am currently taking clients for running evaluations.

***Disclaimer: These shoes were provided free of charge in exchange for a review.  We thank the  people at On Running for sending us a pair.  This in no way affected the honesty of this review. We systematically put each type of shoe through certain runs prior to review. For trainers and performance trainers, we take them on daily runs, workouts, recovery runs and a long run prior to review (often accumulating anywhere from 20-50 miles in the process). For racing flats we ensure that we have completed intervals, a tempo or steady state run run as well as a warm up and cool down in each pair prior to review. This systematic process is to ensure that we have experience with each shoe in a large variety of conditions to provide expansive and thorough reviews for the public and for companies. Our views are based on our extensive history in the footwear industry and years testing and developing footwear. If you are a footwear rep looking for footwear reviews or consultations on development, we are currently looking to partner with companies to assist, discuss and promote footwear models. Partnership will not affect the honesty of our reviews.

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