We spent 9.1 hours reading reviews from experts and users. In summary, this is what runners think:

7 reasons to buy

  • A stretchy polyester yarn makes up the upper unit of this running shoe and it effectively delivers breathable support for the foot.
  • Many reviewers greatly appreciated the flexibility that the 4th version of the Free Flyknit has to offer.
  • The different designs and color schemes placed a lasting positive impression on those who tried it.
  • The underfoot comfort is precise and the cushioning is effective.
  • Reviewers thought that the rounded heel worked pretty well because it encourages a more consistent stride.
  • The Flywire integrations to the sides work really well to enhance the fit.
  • The Nike Free Flyknit 4.0 feels light and fast.

2 reasons not to buy

  • The complaints for this running shoe stem from its initially inconsistent flexibility, though over time the full flexing capability of this shoe will stand out.
  • The mild arch support wasn’t very well-received because some runners felt they deserved more underfoot cradling from this running shoe.

Bottom line

The Free Flyknit 4.0 from Nike is actually one of the most popular running shoes on the market. Many tried it out and felt the comfort, the cool design and the consistent fit that it presented. It is a neutral running companion that offers mild underfoot support, as well as responsible durability.


Update: Nike Free RN Flyknit 3.0
Terrain: Road
Arch support: Neutral
Weight: Men: 7.5oz | Women: 6.3oz
Heel to toe drop: Men: 6mm | Women: 6mm
Pronation: Neutral Pronation
Arch type: High arch
Material: Vegan
Features: Slip-on
Strike Pattern: Midfoot strike
Distance: Competition
Heel height: Men: 23mm | Women: 23mm
Forefoot height: Men: 17mm | Women: 17mm
Brand: Nike
Type: Low drop
Width: Men: Narrow, Normal | Women: Normal
Price: $120
Colorways: Black, Blue, Green, Grey, Multi, Orange, Pink, Purple, Red, White
Small True to size Large
See more facts


A top rated Road running shoe
A top rated Nike running shoe
A popular pick
It has never been more popular than this April
Better rated than the previous version Nike Free 4.0

Expert Reviews

Experts are runners, who post reviews at youtube, directly at RunRepeat or at their own websites. Each expert is categorized from level 1 to level 5 based on expertise. See stats on expert reviews and how we calculate scores here.

Are you an expert? Apply to contribute here.

87 / 100 based on 15 expert reviews

  • 90 / 100 | Kyle Jang

    Nike Free Run Flyknit 4.0: Flexible and breathable for everyday use

    More photos

    The Nike Free Flyknit 4.0 is a great looking shoe. It combines a seamless upper with multiple colors with a sleek, low profile. I would consider the 4.0 a pseudo lifestyle shoe because of all the people I see wearing it while I'm out and about.

    The knit pattern really stands out, and looks great while going for a run, or grabbing a bite to eat. It's no surprise that Nike has continued to make shoes that look very much like it.



    Because of the Flyknit material, this shoe can be bought a tad bit small but will still fit fine. The Flyknit really stretches to fit your foot and is extremely comfortable once it breaks in a little bit. When I went shopping for a pair of these, they only had a half size smaller than my usual size in the color I wanted.

    I decided to try them on, and although they fit a little snug, I decided to keep them. A week or so later, the Flyknit had stretched out to accommodate my foot and I had that sock-like fit that I wanted for this shoe.



    Also, the back of the shoe really locks your foot in and doesn't allow for any heel slippage. The Flyknit 4.0 is a snug fitting shoe that has a great fit due to the Flyknit upper.


    Anything that Nike makes with Flyknit usually has a higher price point. The Flyknit 4.0 has a retail price of $165 CAD, and while that is a bit high, I believe that it's worth it for the shoe that you get.

    It is a very versatile shoe and the Flyknit upper is a great addition. If not for the Flyknit upper, then the most I would pay for this shoe would be $120 CAD. The free midsole is lacking in cushioning compared to Zoom and Air.


    Like any Nike Free Flyknit 4.0 is an extremely flexible shoe. It's flexibility makes it feel as though you are running with barely anything on your foot.

    Combined with the sock-like fit and feather like lightness, this shoe truly exemplifies barefoot running. Don't be fooled by the "barefoot running" advertising however.



    This shoe has enough cushioning to get through those daily runs, unlike some other barefoot running shoes.

    The Flyknit 4.0 is also a fairly comfortable shoe. While not as cushiony as the Zoom or Air midsoles, the Free midsole provides adequate cushioning that should last quite a while.



    However, I personally found that this shoe isn't super responsive while I was doing some speed work with it. Nevertheless, the Free Flyknit 4.0 is a well-performing shoe for various purposes.


    The Nike Free Run Flyknit 4.0 is a sharp looking shoe that combines fashion with functionality. It is very lightweight and has a flexible midsole that makes it ideal for many different kinds of athletes.

    The Flyknit upper is amazing and stretches to fit your foot like a sock.

    This expert has been verified by RunRepeat. Reviews are neutral, unbiased and based on extensive testing.

  • 88 / 100 | RIZKNOWS | | Level 3 expert

    It is lightweight, breathable, thin, and super comfy.

  • 85 / 100 | Packing Lite | Level 1 expert

    Although these are originally aimed at runners, they actually make for a very comfortable working shoe.

  • 95 / 100 | Believe in the Run | | Level 5 expert

    This shoe was an unexpected treat. I am pretty much over minimal shoes at this point.

  • 90 / 100 | Solereview | Level 5 expert

    The heel area’s got a nice upwards slope or bevel for rear-foot strikers; and if you land in the front, a colony of tightly grouped foam hexagons spread loading evenly.

Become an expert

  • The Nike Free Flyknit 4.0 is a running shoe that delivers a comfortable coverage and a performance that’s reliable and consistent. Appealing color schemes are integrated into this shoe, so the runner gets more aesthetic flair when wearing it. It looks cool and it feels very responsive when taken on the roads.
  • The upper unit uses a material that resembles a woven cloth. It’s durable, breathable and very comfortable to the skin. It doesn’t restrict natural movement, so the foot is allowed more flexibility even when wearing the shoe. A snug, but secure fit is handled by the Flywire cables, which connect directly to the lacing system.
  • The mid-sole system utilizes a foam unit that’s soft, responsive and flexible. It has a low-profile height, so it doesn’t limit the movements of the foot. Still, it is able to deliver sure underfoot support that’s consistent and efficient. The 6mm drop and a rounded heel enable a more natural striking of the foot. This version has more cushioning than the Nike Free Flyknit 3.0.
  • On specific areas of the outsole is a durable rubber material that’s made to provide protection against wear and tear. Traction is also a part of this unit’s purpose. Natural flexibility is handled by hexagonal flex grooves.

The Nike Free Flyknit 4.0 has a regular shoe length. It follows the standard measurements when it comes to the men and women’s sizes. Its semi-curved shape allows the natural curvature of the foot to acclimate well to it. The available width is medium.

When looking at the outsole layer, one can definitely notice some durable rubber placed in critical areas where wear and abrasion are most likely to appear. Aside from delivering protection, this rubber also provides traction over the surface.

Hexagonal flex grooves are cut all over the sole unit’s external surface. These grooves allow the platform to move according to how the foot flexes, so natural motion is actually being encouraged.

Waffle pistons are observed in specific sections of the outsole. They give some bounciness to each step, making sure that the foot’s landings and the liftoffs are well-cushioned and supported.

The Phylite mid-sole material is a responsive yet durable foam unit that serves as both the underfoot platform and the outsole unit of the Nike Free Flyknit 4.0. It is not heavy, but it is able to provide sure support for the underfoot. It’s 40% rubber, so it stays strong even after many uses.

The lightweight Flyknit upper technology is one of the most breathable fabrics when it comes to running shoes. It allows air to seamlessly enter the shoe to keep the foot cool and dry. Its woven-cloth-like quality doesn’t irritate the skin, so it stays comfortable at all times. This upper coverage is also used in the Nike Free Flyknit 5.0 and other best-selling Nike running shoes.

The Flywire cables are connected directly to the lacing system. When the shoelaces are adjusted these cables follow suit, making sure that the upper unit is able to wrap around the foot in a snug, but secure manner.

A molded sock liner follows the natural contours of the foot. It supports the underside of the foot, keeping it in place and maintaining constant cradling, even for the arch.


Jens Jakob Andersen

Jens Jakob is a fan of short distances with a 5K PR at 15:58 minutes. Based on 35 million race results, he's among the fastest 0.2% runners. Jens Jakob previously owned a running store, when he was also a competitive runner. His work is regularly featured in The New York Times, Washington Post, BBC and the likes as well as peer-reviewed journals. Finally, he has been a guest on +30 podcasts on running.