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Vibram FiveFingers KSO Review

These are great for runners who can size themselves perfectly and want a barefoot lifestyle shoe as well as a great gym shoe.
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Price:  $85 List | $84.95 at Amazon
Pros:  Inexpensive, multi-purpose, rugged and durable
Cons:  Wonky, sizing is tough and take a long time to break-in
Manufacturer:   Vibram
By Thomas King ⋅ Review Editor  ⋅  Feb 23, 2018
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#6 of 8
  • Running Performance - 30% 6
  • Barefoot Accuracy - 25% 8
  • Comfort - 15% 7
  • Traction - 15% 5
  • Versatility - 10% 5
  • Durability - 5% 7

Our Verdict

Vibram made their name off their FiveFingers and excellent outsoles which are even appropriated by the military for heavy-duty combat boots. However, we feel that in their 10th Anniversary, the Vibram FiveFingers KSO still has some of the same defects as it did at launch with not enough improvements to merit an award. The addition of a few features to prevent sand and rocks getting in these on hikes and minimize blisters helped the shoe, but still did not manage to put it above its competitors.

Seasoned barefoot runners and minimalists who have perfected the forefoot strike will find these a companion around the gym or on a short hike. This is the ideal shoe for a cross-trainer that wants a shoe flexible enough to wear on the trail, short runs, and at the gym.

Compare to Similar Products

Our Analysis and Test Results

At 6.8 ounces per shoe in men's US size 11.5, these are surely lightweight, and with the FiveFingers design and minimal outsole padding and zero drop ratio, these are among the highest scorers for Barefoot Accuracy in our review. The FiveFingers KSO is perfect for the minimalist seeking out a lightweight shoe for short hikes or the workout junkies seeking a true barefoot experience.

Performance Comparison

Wet rocks on the river is not the KSOs wheelhouse. They slip quite a bit on flat  wet surfaces.
Wet rocks on the river is not the KSOs wheelhouse. They slip quite a bit on flat, wet surfaces.

Running Performance

You'd be correct in thinking that this shoe does very well on short hikes and as a flat shoe for gym-rats and squatters seeking to break the trends in the gym for flat-bottom shoes. None of the other shoes in our review do as well for wearing around the gym, but we only find truly confident people braving the looks you get for wearing the FiveFingers design. However, if you can get over their unique look, these are the best in this review for someone looking for a barefoot squat shoe with a bit more multi-purpose than gym-rat uni-tasker shoes.

Barefoot Accuracy

Nothing is more accurate at giving a barefoot experience than a glove for your foot that provides some padding. The abrasion-resistant stretch polyamide stands by its name of minimizing hot spots and blister areas, which is necessary because we found most FiveFingers users do not wear socks with their shoes. The accuracy that Vibram brings to the KSO even outshined the accuracy of other shoes with thinner feeling outsoles.


For a shoe to give the option of running without socks, it better have superior design to prevent hot spots and blisters. Vibram has been doing this foot-glove for a while, and they show it here. The reinforced heel patch made of a thicker supple material eliminates the abrasive heel hotspots runners have complained about when going sockless in other FiveFingers designs. However, the persistent issue of making a glove-like foot mold still has not been solved with this latest iteration. Users have complained that some models in the past ran too small, but we found these KSOs ran large and left far too much room on each toe while fitting perfectly everywhere else.

This velvet-like material on the heel at the base of the Achilles tendon works great at preventing hotspots and abrasion.
The fit of these shoes is always very specific  so make sure you get the right feel so your toes fit correctly.


The "Keep Stuff Out" moniker works here, and it almost feels like cheating because no shoe has as glove-like a fit as this. But with an essentially smooth bottom, it slips and slides on cobbles outside my gym, let alone on a short hike. We noticed the other smooth bottom shoes experienced similar slippage. If you are looking for a versatile shoe in and out of the gym, we recommend looking elsewhere. We found that the hikes you ought to do in these shoes should stick to relatively flat terrain with lots of gravel and grass to break up the ground because you will slip and slide on smooth rocks, especially if it's even just a little damp out.

Here  our reviewer is quickly running off the rocks to more uneven terrain where the KSO can grip the ground better.
Here, our reviewer is quickly running off the rocks to more uneven terrain where the KSO can grip the ground better.


Although its namesake acronym might suggest that this shoe will perform well on trails, we believe that the KSO is best suited to stick to the roads, or maybe subtract one step further and stick to the gym. Their lightweight mesh-upper is well-suited to running in the heat, but even in a light drizzle, we found these shoes to be almost too slick to run in the rain. Comments on style choices aside, we couldn't quite bring ourselves to run around town in these shoes — unless we were running quickly and not running errands.

Getting a workout with the Vibram FiveFinger KSO
Getting a workout with the Vibram FiveFinger KSO


Many users have complained about their durability, but after dozens of miles of runs and hikes, we noticed no depreciation in their quality or performance. In fact, we stand by the report of many other FiveFingers users, that you should expect to have these shoes around for years and years with only maybe an occasional need to give them a light wash.


These are a fair price for what you get: a shoe that can deliver on runs, hikes and at the gym. These are one of the cheapest pairs of shoes in our review and offer some of the most flexibility in where the shoe shines.


If you are looking for the ultra-barefoot experience and have the confidence to stand up to a few sideways glances at the gym, you will find, as many others have, that you know a secret they don't. This shoe can perform and will outlast anything else on the market. After such a long time on the market, these shoes are still pretty great, but other companies have come forward in a big way since the first FiveFingers models and are starting to outpace them.

Thomas King