We spent 10 hours reading reviews from experts and users. In summary, this is what runners think:

8 reasons to buy

  • Many runners have noted that the Saucony Fastwitch 9 feels lightweight, thus ensuring a comfortable ride.
  • Some users were happy on how well the shoe's grip performed on road terrains while providing a smooth ride.
  • A number of wearers claimed the Fastwitch 9 to be a fast shoe, which is great for a running shoe that is aimed at high mileage runs.
  • Most users liked the shoe's responsiveness. They claimed its good responsiveness resulted in pure speed during their road runs.
  • The shoe's toe box was also praised as it is spacious enough to allow the feet to splay naturally during the runs.
  • A few testers mentioned how the shoe's tongue was comfortable, had an elastic sock-like fit, and securely stayed in place.
  • The shoe's outsole durability was also praised by most of its wearers, thanks to its PWRTRAC outsole material.
  • One reviewer thought the styling on the Fastwitch 9 was much improved than the Fastwitch 8.

3 reasons not to buy

  • A few of the Fastwitch 9 users mentioned that the fit of the toe-box is not tight and not wide enough.
  • According to a couple of wearers, the shoe's outsole was a bit complicated as it allowed water and debris to enter, which became an issue for several occasions.
  • Also mentioned by some users is that the Fastwitch 9 had too much cushioning for a racing shoe.

Bottom line

The new Fastwitch 9 with its lightweight SSL midsole and PWRTRAC outsole gives great cushion and traction that most runners admire. Majority of its wearers also liked the engineered mesh upper that provides a breathable fit that they found very comfortable.  Although not well received by runners who are flat footed and a few unfavorable reviews about the shoe's tight toe box, majority of runners still laced up, pushed the pace, and won races in their all-new Fastwitch 9.


Terrain: Road
Arch support: Stability
Weight: Men: 6oz | Women: 5.1oz
Heel to toe drop: Men: 4mm | Women: 4mm
Fit: Medium forefoot, Medium heel, Medium toe box
Pronation: Overpronation
Arch type: Medium arch
Material: Mesh upper, Rubber sole
Features: Breathable
Strike Pattern: Forefoot strike
Distance: Competition
Heel height: Men: 19mm | Women: 19mm
Forefoot height: Men: 15mm | Women: 15mm
Brand: Saucony
Type: Low drop
Width: Men: Normal | Women: Normal
Price: $100
Colorways: Black, Green, Orange
Small True to size Large
Forefoot fit
Narrow Wide
Heel fit
Narrow Wide
Tight Roomy
Stiff Flexible
Warm Breathable
Firm Plush
Durability 8/10
Comfort 9/10
Traction 7/10
See more facts

Expert Reviews

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96 / 100 based on 3 expert reviews

  • 99 / 100 | Charles S.

    So light they feel like cheating: Saucony Fastwitch 9 review

    More photos

    The Saucony Fastwitch 9 is a stability road shoe that is so much lighter than competing shoes, lacing up a pair on race day almost feels like cheating.


    Who Fastwitch 9 is perfect for

    Shoes like the Fastwitch 9 are aimed at runners with mild-to-moderate overpronation who find stability features like a medial post beneficial in mitigating injuries and improving running form.

    Typically, however, these stability features add extra heft, so finding lightweight stability shoes for fast track workouts, tempo runs, and races have until recently been a real challenge, with stability shoes feeling more like cement trucks than Ferraris.

    Fortunately, as the market and engineering of running shoes has become more sophisticated, the number of race-ready stability shoes has ballooned to the point that the challenge for consumers is no longer finding a lightweight stability option but choosing the best lightweight stability shoe.

    Today, virtually every major shoe company—Saucony, Asics, Adidas, Nike, New Balance - offers a lightweight stability shoe (see “The Competition” section below).

    Yet in my experience, the Saucony’s Fastwitch 9 beats them all, being dramatically lighter than the offerings from each of the aforementioned competitors at just 6.7 oz for a men’s size 9, with a perfectly designed upper and outsole attached to a flexible layer of springy yet firm midsole foam.

    Taking them out of the box is an immediate indication: the cardboard packaging feels like it weighs more than the pair of shoes themselves. Lacing them up just makes you feel fast.

    The Fastwitch 9 is such a lightweight, go-fast shoe, that even some neutral runners who miss the firmer, more responsive feel of older models of the Saucony Kinvara have adopted the Fastwitch for everything from 5K to marathon races.

    In-depth review, from top to bottom


    The Fastwitch 9’s upper is terrific. Minimal use of overlays keeps it light, breathable, and form-fitting. It is a significant improvement from the somewhat overlay-heavy Fastwitch 8.

    While it lacks overlays for weight-saving, breathability, and accommodating fit, the Fastwitch 9’s upper does have a lightweight but firm heel counter to keep feet locked in place and stable. While many overlay-free uppers (like the one in the Nike Free Run) can feel floppy and cause feet to slip around.

    The Fastwitch 9’s use of a heel counter works well with its overlay-free upper so that the shoe feels comfortably sock-like and stays comfortably in place during rapid-turnover sprints.



    The only disadvantage to the Fastwitch 9’s upper is that being so minimal, it wears down and starts to lose its snug fit and form after fewer miles of use (around 100-200 miles) than long-distance trainers like the Saucony Liberty ISO.

    That said, the upper’s lower durability relative to heavier everyday trainers is an expected tradeoff to get the shoe to be so light. In my opinion, the tradeoff is absolutely worth it, especially if you’re reserving the Fastwitch for its intended purpose of shorter mileage tempo runs, track workouts, and races.

    I also found the Fastwitch 9’s upper was more durable than competing lightweight stability shoes like the Nike Lunarglide 9 that I found started to lose snugness in its upper after as few as 50 miles of wear.


    The Fastwitch’s midsole is perfect for speed work. It is firm and responsive, and you can feel every ounce of energy goes into propelling you forward, not being wasted squishing down a soft foam.

    The midsole’s forefoot design also has a bit of upward curve to encourage quick turnover during up-tempo runs. Despite being firm relative to long-distance trainers, the midsole’s stack height still has enough cushioning to be comfortable up to around a half marathon distance when running on hard concrete (or up to a full marathon for particularly efficient, lightweight runners).

    The midsole’s 4mm heel-toe drop was also a great choice by Saucony, making the Fastwitch a good option for a wide range of running gaits anywhere from heel to forefoot strikers.



    Of course, the highlight of the midsole, and what separates the Fastwitch from neutral race day shoes like the Saucony Kinvara are its stability features. Here, the Fastwitch 9 has just enough support to keep mild-to-moderate overpronators comfortable with the use of a dense foam post that reduces excessive flexion in the medial arch.

    In addition, the Fastwitch’s midsole is designed with a bit of outward flair from the top to the bottom to help keep feet stable through the mid-stance phase of the gait cycle to help cycle efficiently through toe-off.


    The Fastwitch’s outsole is perfectly grippy on roads and tracks, with grooves positioned in all the right places to allow forefoot flexion while keeping the midfoot rigid and secure. The design of the outsole, therefore, works well with the midsole’s medial post to further mitigate any instability while running.



    I really appreciate that Saucony decided to keep durable outsole rubber along the full length of the shoe. This choice runs counter to many brands who have taken to getting rid of some or all of the outsole material in speed-oriented shoes to save weight since this dense rubber is usually the heaviest material used in a running shoe.

    Getting rid of outsole rubber might be an easy way to drop a shoe’s weight, but the design choice has two problems. First is the loss of grip. Second is that it leaves the midsole foam vulnerable to abrasion from the ground, quickly breaking it down since the midsole foam is left rubbing directly against the pavement with every step.

    As a result, I’ve found shoes without full rubber outsoles like the Nike Lunarglide 9 have much less grip and wear down dramatically faster than shoes like the Fastwitch.

    The competition

    If you’re considering running in the Fastwitch, it is because you’re looking for a lightweight race day or speedwork shoe with a touch of stability.

    That means after narrowing down the options to the stability shoe category, the single most important variable will be weight, and at 6.7 oz for a men’s size 9, the Fastwitch 9 has all of the competition beat:

    • New Balance 1500v5 (8.3 oz)
    • Brooks Asteria (8.3 oz)
    • Asics DS Trainer 24 (8.7 oz)
    • Nike Lunarglide 9 (9.3 oz)
    • Adidas Adizero Tempo 9 (9.8 oz)



    Other than weight, all of these shoes have similar lasts (fairly narrow, race-fitted uppers), levels of stability (posted, but only mildly), and prices (around $120 retail). The only two reasons I can think of that one might go with another shoe in this category are:

    1) You prefer a softer, plusher midsole, in which case the Asics DS Trainer 24 or Nike Lunarglide 9 might be worth the added weight, or

    2) You prefer a more traditional heel-toe drop, in which case the Nike Lunarglide 9 or the Adidas Adizero Tempo 9, each with 10mm drops, will be preferable to the Fastwitch’s more minimalist 4mm drop.

    The Saucony Fastwitch 9 is a perfectly speedy, responsive, lightweight stability shoe for any mild-to-moderate overpronators who want to run fast paces on track, tempo, or race days.

    Compared to competing shoes, the Fastwitch 9 is lighter with a grippier, more durable outsole. It also features an impressive upper that keeps the foot locked in place without the use of any bulky or restrictive overlays.

    The one downside of the shoe is a lack of durability compared to heavier, long-distance training shoes, but if you reserve the Fastwitch for its intended purpose of lower mileage speed workouts and races, then this weight-for-durability tradeoff is absolutely worth it.

    In sum, if you need to run fast while mitigating pronation, the Fastwitch 9 is the best option on the market.


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

  • 92 / 100 | Ethan Sunseri | Level 1 expert

    it's a very simple very lightweight and for only $100 I'd say you're getting a pretty decent deal you know if you're gonna be doing a lot of road work a lot of track work speed sessions and you're gonna be racing maybe half marathons

  • 90 / 100 | Doctors of Running | | Level 1 expert

    this shoe as it is not only the lightest stability racer, but the fastest in my opinion. The snug adaptable mesh provides a great breathable hold on the foot. The midsole is responsive and extremely light. Finally the dual density medial post provides light stability along with other elements that will keep you on the right track even when you fatigue. A great redesign that is well worth a look for newcomers as well as those with extensive experience with the Fastwitch series

Become an expert

  • The eighth edition of the Fastwitch lives up to its known legacy of stability and speed. The new Fastwitch 9  now features a lightweight engineered mesh upper that offers both support and breathability. The engineered mesh upper is also supportive in providing a closer fit compared to its predecessor, the Fastwitch 8. Despite the closer fit, this does not in any way restrict the shape or feel of the shoe when running.
  • The updated mesh upper now also presents the huge Saucony logo and ombre finish to give the Fastwitch 9 its freshest look to date.
  • This Saucony running shoe's midsole now features a lightweight construction and responsive SSL EVA midsole for energy return. This helps the shoe to feel more agile and responsive on every stride. This also keeps the cushioning on the firmer side, and the SSL EVA material also provides excellent protection for runs at a variety of speeds.
  • The outsole of the Saucony Fastwitch 9 has also been completely updated and redesigned. The midfoot post is still found present in this new model, but the remainder of the sole has now been replaced with a triangular design. The reason for this is that the triangular design creates a smoother ride and better flexibility in the forefoot. This also allows a very smooth toe-off while also offering excellent traction on different types of surfaces, even on wet roads.
  • The outsole update on the Fastwitch 9 does not stop there; it also uses the Saucony PWRTRAC technology which is responsible for the shoe's traction. This provides both great acceleration and control.
  • Since it is now on the 9th version, the Fastwitch 9 has also dropped its weight further to 170 grams (based on Men's shoes). Despite the reduction of weight, the shoe proves to remain snappy, supportive, and responsive ride on all types of road runs.
  • Lastly, the shoe's 4mm offset gives the shoe a better performance edge that lets the body naturally control the ride with less reliance on cushioning or support.   

The fit and sizing of the Fastwitch 9 has been released to be true to size with snug fit for racing. Made to come in medium width for men which is D and for women, it is in medium width B.

The shoe's heel was made to be snug to hold the foot well with an almost non-existent heel counter. The midfoot section offers a bit more space for the foot but it then tapers off into the forefoot which is not too wide. This is where the engineered mesh upper comes in slightly adjusting the stretch to accommodate to the wearer's forefoot. Overall, the Fastwitch 9 has a customized fit feeling and it is also not too narrow.

The Saucony Fastwitch 9 use the PWRTRAC rubber outsole which provide three time better traction than the usual rubber.  This enhances the shoe's grip enhancing every pounce and step. The PWRTRAC is a durable rubber that also gives exceptional abrasion resistance allowing for a longer wear of the shoe.

The Fastwitch 9 utilizes a full-length CMEVA midsole to provide cushioning for increased impact protection and shock absorption.

The Fastwitch 9 is constructed with a medial post that is  engineered to help slow the rate of overpronation. This medial post device is firmer than the rest of the midsole material providing medial support for increased stability.

Within the shoe's midsole is the SSL EVA which provides lightweight responsiveness.

Engineered with a 4mm heel-to-toe differential, the Fastwitch 9 offers a faster performance and natural form which encourages an efficient, continuous and positive gait cycle from heel strike to toe-off.

Just like the popular Saucony stability running shoe, the Saucony Guide 10, the Fastswitch 9's upper consists of engineered air mesh that combines breathability and support. This allows air to fully permeate the entire footbed to guarantee that  the feet stay cool and comfortable when the temperature goes up.

A strong, lightweight material is also melted to the upper, which allows for few layers in the shoe shedding weight, making it more flexible resulting in a seamless upper which reduces skin irritation and chafing.


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.