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Xero Shoes HFS Review:
As Close to Barefoot as You Can Get?
By Contributor Andrea Myers and Chief Editor Matt Klein

Xero was started by a husband and wife team who were inspired by Born to Run. They began making running sandals and have since expanded to a full line of zero drop, minimalist shoes for running, hiking, and casual wear. The HFS is Xero's road-specific running shoe. It has a 24-month warranty and an unbelievable 5000-mile sole warranty. With a highly flexible sole that can be rolled into a ball and an ultra-low, 8.5mm stack height, the HFS feels as close as you can get to barefoot running while still having the underfoot protection of a rubber sole.

Xero HFS
Price: $119.99 at
Weight: 6.8oz, (men's size 9), 5.8oz, (women's size 7)
Stack Height: 8.5mm with insole, 5mm without insole
Drop: 0mm
Classification: Minimalist road running shoe


Matt: The Xero HFS is a super flexible, durable and minimal/barefoot-inspired road running shoe. Featuring wider and anatomic fit, the mesh upper provides plenty of room and breathability. An 8.5 mm stack height provides protection and solid ground feel, with an option to drop to 5 mm without the insole. The shoe flexes in all directions, giving your foot the freedom to do as it wants while still providing some mild protection. The Xero HFS is one of the best minimalist running shoes out there for simulating barefoot running while providing defense from environmental hazards.

"The HFS is the only zero drop shoe I have tried that actually felt like it was doing nothing except protecting the sole of my foot from the elements."

Andrea: I have run in many zero drop shoes in the past, including the Altra Escalante, Escalante Racer, Torin, Solstice, and Timp; the Topo Magnifly 4; and the Inov-8 Trailtalon 235. None of them are as minimal as the Xero HFS due to the HFS's very low stack height and incredibly flexible sole. The HFS is the only zero drop shoe I have tried that actually felt like it was doing nothing except protecting the sole of my foot from the elements. I definitely found myself landing differently than I do in any of the above shoes due to the lack of cushioning or stability in the midsole and outsole of the HFS. I enjoyed running in this shoe and I think it is as close as a person can get to running barefoot while still having something between your foot and the ground.


Matt: The Xero HFS fits a half size small and I was sent a size a men's US Size 10.5. I normally wear a men's US size 10, but found the size 10.5 to fit better with a full thumb's width between my toe and the end of the shoe. This did feel almost long at first, but the protective toe guard makes the shoe fit a bit shorter and more true to size. The width is on the wider side with the anatomic shape. The forefoot fit me perfectly with plenty of room for toe splay. The midfoot fits wider, so I had to tighten down the laces as much as possible to get a secure fit. I was able to achieve this with additional help from the midfoot straps that add additional security. The heel fits more normal and there is no heel counter in the rearfoot. Due to some additional stitching and reinforcement on the outer aspect of the upper, the heel still retains its shape. I did not have to lace lock the shoe due to being able to lock down the midfoot well (although I really had to tighten the laces). The tongue is free-floating but is connected to the laces. It stayed securely in place and has the perfect amount of padding (not too little and not too much). The Xero HFS is an excellent shoe for running without socks if you use the insole. There is an internal mesh that is comfortable against bare skin with no seams. This does create a slightly longer fit, so those wanting to go sockless should consider going true to size. Without the insole, there is exposed stitching throughout the length of the shoe, so wearing socks would be a far better option.

Andrea: Xero recommends sizing 1/2 size up in the HFS, so they sent me a women's 10 instead of my usual  9.5. Xero shoes are foot-shaped, with a wide toe box that allows plenty of room for toe splay. I found the width of the toe box to be comfortable without being sloppy. The length of the 10 fit perfectly with a full thumbnail width from the end of my big toe to the front of the shoe. The fit of the midfoot can be dialed in with midfoot straps that attach to the laces. I found these straps to be key because there are no other features in the upper that provide stiffness or stability. The shoe can be rolled in ball or twisted like a washcloth due to the complete lack of stability features. The tongue has a surprising amount of padding for a minimalist shoe and is not gusseted, but the laces hold the tongue securely in place through a loop near the top of the tongue. There is no heel counter, but the internal collar has a moderate amount of padding, which does a nice job of conforming to the heel without limiting motion. The 3.5mm insole provides very mild cushioning while still allowing for exceptional ground feel. The HFS is designed to be used with or without the insole, depending how much of a barefoot feel a runner is looking for. I found landings to be too harsh without the insole, so I did the vast majority of my runs in the HFS with the insole. Overall, I was very pleased with the fit of the shoe and found it to be very comfortable for both running and walking.


Matt: The HFS provides a minimal and highly flexible ride. The 3.5 mm insole and 5mm outsole provides excellent ground feel while still maintaining protection. This does require softer and more careful landings as all stones and obstacles on the ground can be felt. Weirdly, the insole still provides a mildly soft underfoot sensation while walking, but this is not a cushioned shoe at all. The sole flexes in all directions, letting your foot do what it wants to do. This makes it somewhat adaptable to a variety of uses. I have used the Xero HFS on a variety of surfaces, but found that works best on the road and indoor areas. The outsole grip is fantastic even on wet pavement and there is no wear on the outsole after 20 miles of running and many more walking.

The lightweight makes the Xero HFS excellent as both a minimal daily training shoe and uptempo/racing shoe for those looking to run fast in as little as possible). I was able to do strides on road and found the shoe easy to turn over in once my legs got used to firm ground. The slightly cushioned insole provided some mild natural snap, although those looking to run fast in this type of shoe will need to ensure they have optimal mobility and strength in all the right areas (1st MTP joint, talocrural joint, calf muscles and intrinsic foot muscles). I was not able to take the HFS for longer mileage given my own limitations but found the shoe retained its protection even after 10-12 hour days walking, standing and moving in clinic. The traction on the outsole provided enough grip to turn quickly, lift and do just about any physical activity. Those looking for a minimal running or multi-purpose gym shoe will find what they need in the Xero HFS.

Andrea: The HFS provides the greatest barefoot feel of any shoe I have tested. It feels like a completely stripped down road flat. My road flat of choice in the past has been the Saucony Type A8, which has a stack height of 17mm heel/13mm forefoot. The Type A8 feels like a daily trainer compared to the HFS. You have to be very careful with your landings in the HFS because you will feel every rock in the road or crooked sidewalk. This is the point of the HFS: to provide the greatest ground feel and proprioception possible, which it delivers in spades. I really enjoyed this feature of the HFS because it made me feel more connected to the ground both mentally and physically as well as a greater overall awareness of my body while running.

I tested the HFS at easy paces and during strides at 5k to mile pace. At easy paces, I had to be more aware of how I was landing, especially on the sidewalks on my usual routes that are in poor condition. I liked the extreme flexibility of the outsole and the excellent grip of the rubber outsole. I had no issues with traction, even on sand covered winter roads. At faster paces, the shoe felt more like a very pared down racing flat and felt natural and responsive. Due to the extreme flexibility of the outsole and the 0 drop, the shoe places much greater load on the 1st MTP joint as well as the calf muscles. To run in the HFS, a runner should have at least 60 degrees of 1st MTP extension and be able to do 20-25 single leg calf raises. Runners new to zero drop shoes like the HFS should progress their mileage and intensity slowly and cautiously to avoid potential calf, ankle, or foot injuries. Prior to testing the HFS, I had been running regularly in the Topo Magnifly 4, and I had to be cautious not to overdo it in the HFS due to the significant difference between the two shoes in terms of stack height, sole stiffness, and toe spring. Due to the lack of underfoot protection, I limited my runs in this shoe to <1 hour.


Matt: The Xero HFS is a barefoot-inspired shoe and has no stability features. The sole/last is wider and anatomic, which provides excellent ground contact throughout the length and width of the foot. The upper midfoot straps lock the foot down well without being overbearing, creating a solid level of security once the laces are optimized. There are no stability features overall as this shoe is meant to let your foot do what it wants to do.

Andrea: It almost goes without saying that the HFS has no stability features. Runners need to have excellent calf strength and 1st MTP range of motion as noted above. I would like to note that the upper fits exceptionally well due to the midfoot straps that attach to the laces. This is a really nice feature that allows the fit of the shoe to be dialed in based on the shape of your midfoot while still allowing the highest level of upper and outsole flexibility. 


The Appeal of Zero Drop Shoes, by Contributor Andrea Myers
I would like to emphasize the major differences between the HFS and other popular zero drop shoes. We write a lot here at DOR about the importance of gradually transitioning to zero drop shoes, but I would also like to highlight the importance of gradually transitioning within the zero drop category. There are many zero drop shoes on the market that have stack heights above 20mm: Topo Magnifly 4 (25mm), Altra Rivera 2 (26mm), Vanish Carbon (33mm), Provision 6 (28mm), Escalante 2.5 (24mm), and Escalante Racer (22mm). The ride of these shoes is much different than the HFS because the higher stack height and greater amount of cushioning will be more forgiving of harder landings and heel striking. Many people are attracted to zero drop shoes because of the possible benefits of barefoot running, including lower ground contact forces, a more forward initial contact (midfoot or forefoot strike), and reduced stress on the knee and hip. Some research suggests that these benefits are likely to be seen only when a person is actually running barefoot (Hollander et al 2015, Bonacci et al 2013), although these studies compared 4-6mm drop minimalist shoes to very low stack zero drop shoes and true barefoot running. The presence of more than a small amount of material between the foot and the ground may result in biomechanics that are more similar to running in a traditional shoe. The very minimal stack height and highly flexible sole of the HFS (8.5mm with the insole and 5mm without) may result in gait characteristics that are more similar to barefoot running. There are no studies that I could find specifically on the HFS, but a study on the Vibram Classic FiveFinger found similarities in several measures of running biomechanics between the shoe and actual barefoot running (Squadrone et al 2009). It would be interesting to see studies that specifically compare zero drop shoes that have <10mm of stack height and those that are >20mm. The take-home message here is that if you are currently running in a zero drop shoe with >20mm of stack height, be careful if you want to try a very low stack shoe like the HFS.


Hollander K, Argubi-Wollesen A, Reer R, Zech A. Comparison of minimalist footwear strategies for simulating barefoot running: a randomized crossover study. 
PLoS One. 2015;10(5):e0125880. Published 2015 May 26. doi:10.1371/journal.pone.0125880

Saunders PUHicks A
, et al. Running in a minimalist and lightweight shoe is not the same as running barefoot: a biomechanical study.

Ridge, S. T., Olsen, M. T., Bruening, D. A., Jurgensmeier, K., Griffin, D., Davis, I. S., & Johnson, A. W. (2018). Walking in minimalist shoes is effective for strengthening foot muscles. 
Faculty Publications. 3159.

Squadrone R, Gallozzi C. and 
Biomechanical and physiological comparison of barefoot and two shod conditions in experienced barefoot runnersJ Sports Med Phys Fitness. 2009; 49: 6– 13.


The Xero HFS is a fantastic minimal/barefoot-inspired shoe. Based on the accomodating upper, great breathability and solid underfoot feel, I have no major recommendations outside of adjusting the sizing. This may require modifying the toe guard as well, but that does give some structure to the toe box. 

Andrea: The HFS is designed to be a barefoot shoe and it truly excels at this purpose. With this in mind, I have no major recommendations for improvements to the shoe. I would recommend that Xero improve its sizing so it is more consistent with other brands. My other recommendation is to improve the interior of the shoe for those who choose to remove the insole and run sockless. The interior stitching is raised in some areas and could potentially cause skin irritation or blisters. Overall, this is the best truly barefoot style shoe I have tried.


Matt: The Xero HFS is for those looking for a barefoot-inspired/minimalist shoe with solid ground feel, excellent flexibility, and an anatomic and slightly wider fit in a shoe that can handle a variety of activities on road and indoors. The minimal nature of the shoe will require anyone interested to have appropriate amounts of mobility and strength of their lower extremity. Those without prior experience in this category should consider wearing them for walking first, as initial evidence has suggested that alone can be effective for strengthening the intrinsic foot musculature (Ridge et al., 2018). I used this shoe for exactly that purpose over several weeks and have slowly begin to integrate running in this shoe. This type of footwear takes time to adapt to, so make sure you give your body the time it needs to transition.

The HFS is for runners who are looking for a barefoot style shoe and have sufficient great toe range of motion and calf strength to run in such a shoe. Due to its extremely low stack height and outsole flexibility, it is a more aggressive than any Altra or Topo shoe and should be approached with caution. Check out this DOR video on how to transition to a 0 drop shoe.

If you are a runner who currently trains in a zero drop shoe and are looking for something with maximal ground feel and flexibility, the HFS will be an excellent choice.


The Xero HFS accomplishes the goal of minimalism and allowing unabated motion of the foot. The rubber outsole is protective against any small rocks, but besides that protection, the design allows for movement of the sole in any direction. Additionally, the wider toe box allows for toe splay and will accommodate many different foot types. We have seen a number of studies show increased injury rates, mostly metatarsal stress fractures, when runners transition too quickly to minimalist shoes. On the flip side, running in minimalist shoes has been shown to increase foot strength. This is because the demands placed on the foot are much higher in minimalist footwear, and running itself is a very high demand activity. When demands are high, the body will either adapt or fatigue. If you adapt, you get stronger. If you fatigue and push through, it may result in injury. Given the higher demands placed on the foot with minimalist footwear, it is highly recommended to very gradually transition to running if you are making a move to minimalist footwear. Even the strongest proponents for minimalist footwear recommend a "Graded Loading Program" such as the one proposed by Warden et al. that includes a walking program before even initiating very small amounts of running.

For me, these shoes a great option for work. The demands and impact of walking and standing are much lower than running, and utilizing these shoes for work can begin this strengthening and conditioning of the foot through graded loading. I have been using this shoe at work for the last two weeks, and the accommodating upper allows for me to even perform my toe yoga, toe splays, and doming exercises throughout the day in addition to getting the loading through simply walking and standing. We say it all the time around here, but shoes are tools, and even if you don't plan on making a full transition to minimal footwear, you can still glean benefits from daily use of shoes like these if done safely and correctly.

- Senior Contributor Nathan Brown


Davis, I. S. (2014). The re-emergence of the minimal running shoe. journal of orthopaedic & sports physical therapy, 44(10), 775-784.

Warden, S. J., Davis, I. S., & Fredericson, M. (2014). Management and prevention of bone stress injuries in long-distance runners. journal of orthopaedic & sports physical therapy, 44(10), 749-765.


Fit: B+ (Anatomic toe box. wider fit but able to lock down midfoot thanks to secure straps. Fits a half size small, so will need to size up. Upper protective and a bit thicker than expected )
B+/A- (Excellent ground feel while still having a soft insole. Extremely flexible outsole that feels great running at higher speeds for short distances or longer efforts if used to barefoot/minimal shoes. Not enough cushioning or protection for me to use personally beyond short mileage. )
Stability: N/A (Not an applicable category as this is a minimalist/barefoot inspire shoe. )
DPT/Footwear Science: B (Midfoot straps lockdown the foot well while still providing an anatomic fit. I like the additional insole cushioning, but this may change mechanics compared to running barefoot. A solid choice for those looking to transition into barefoot running as a start, but transition time and additional proprioceptive training are needed.)
Personal: A- (My go to shoe for non-running activities. Comfortable for long days in clinic and outdoor recreational activities. Not enough for me personally to run longer distances at this time, but excellent for walking, gym and shorter runs working on foot strength and mechanics)
Overall: B+ (One of the top barefoot inspired/minimalist shoes out there. Slight sizing issues (go a half size up) but good anatomic fit, upper security and solid underfoot feel without being too harsh)

Fit: A- (Midfoot straps provide excellent lockdown, anatomical toe box allows toe splay without being sloppy, extremely comfortable rearfoot, minus 1/2 grade for sizing issues)

Performance: B+ (Excellent ground feel and outsole flexibility, feels very natural at faster paces, but isn't protective enough for me to use for runs >1 hour)
Stability: D (Not designed as a stability shoe, midfoot straps do provide excellent upper lockdown)
DPT/Footwear Science: B+ (Runners who are accustomed to higher stack, 0 drop shoes should be cautious when transitioning to the HFS; the HFS is likely to mimic true barefoot running conditions)
Personal: B (I enjoyed testing this shoe, but it isn't protective enough for me to keep in my weekly rotation)
Overall: B+ (For those looking for a truly barefoot shoe, it is an A+. Grade given because its use is limited to a smaller number of runners due to biomechanical demands)



Price: $119.99 at

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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 Xero Shoes 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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