Ultrafly 4
Product Overview
The best version yet of our fan favorite all-purpose daily trainer has landed, now featuring even more comfort and more sustainable materials. The sleek and comfortable upper features a recycled engineered mesh and our signature roomy toe box. The ZipFoam™ midsole delivers lightweight resilience and response, while an external TPU heel counter and EVA medial post offer light guidance. Perfect for those seeking light pronation support with a smooth and comfortable ride.
Specs
- Best For:Road Running
- Stack Height:28mm (heel) // 23mm (forefoot)
- Heel to Toe Drop: 5MM
- Weight:9.6 OZ (M9)
Why We Love It
5MM Drop
Our highest available drop allows you to access natural running with more under-heel cushioning.
Recycled Materials
Keeping sustainability in mind to help keep waste out of landfills.
Roomy Toe Box
Anatomical toe box allows toes to spread naturally and comfortably.
More Cushioning and Resilience
Proprietary midsole compound which is springier than EVA and offers more rebound over the life of the shoe.
In The Press
Topo leaned into the strengths of the UF3 and made an incredible upper even better.
"Foot shape shoe with nice wide toe box, very comfortable luxurious feeling upper, low drop without being 0, medial and heel support, decent traditional feeling midsole. If that ticks your boxes, this is the shoe for you."
Sizing
Most Liked Positive Review
Fits and feels great
I use these all the time, both for everyday use and for walking. They fit great, the toe box is the best I've ever found. With a broken 5th metatarsal that now has a plate and pins, it the only shoe that fits without pain as it's support is perfect. I actually own 3 pairs in different colors and wil...
Most Liked Negative Review
Why an incomplete sole?
Really like ths3s shoes. Fit and finish of them is great Like the toe box and less rise than other shoes. But Topo what are you doing?this is their only stability shoe and the forefoot of the sole is uncovered foam. Why? This area wears out much yicker than the shoe itself. If they continued t...
Reviewed by 10 customers
Fits and feels great
I use these all the time, both for everyday use and for walking. They fit great, the toe box is the best I've ever found. With a broken 5th metatarsal that now has a plate and pins, it the only shoe that fits without pain as it's support is perfect. I actually own 3 pairs in different colors and will buy another pair soon.
Extremely Comfortable Shoe
Verified Buyer
Comments about Ultrafly 4
I bought these for general all around wear. They are one of the most comfortable pairs of shoes I've ever worn. They are very light, the fit is true, and they offer good general support.
Great Running Shoes!
These are outstanding running shoes. I have a mild overpronation which these handle perfectly. Not to soft or firm. A big thanks to my local running store, Corey at Mountain Running Company for helping me find these! Love these shoes!!
Nice shoe. Just not for my feet.
Verified Buyer
Comments about Ultrafly 4
I have very flat and straight feet. These were simply not straight or wide enough to fit comfortably. Perhaps a wide would work.
Why an incomplete sole?
Really like ths3s shoes. Fit and finish of them is great Like the toe box and less rise than other shoes. But Topo what are you doing?this is their only stability shoe and the forefoot of the sole is uncovered foam. Why? This area wears out much yicker than the shoe itself. If they continued the abrasion resistant tough part of the sole through the whole under side it'd be great. With the exposed foam...not worth it. I tried two pairs because I like the shoe and the minimal rise but won't buy another. I'm a 36 year old runner...I need some support. Have the ultraventures for hiking and trails. Great shoe but too stiff to wear on the road for me.

Disappointed in width. Need more narrow arch.
Verified Buyer
Comments about Ultrafly 4
I need this shoe in a womens fit but you don't make W13/ 13.5. Toe box is fine but really not narrow enough in arch area . I keep lacing it up tighter and it the loosens up. So I do think it is a good shoe but the sizing for me is not great. Actually depending on how far I go my feet hurt a little afterwards.
Overarched & firm midsole hurt foot
After 100 km of running with these shoes, I can tell that those shoes are hurting especially after long runs. The midsole is quite curvy with an arch higher than usual. Add to this the firmness of it and your midfoot starts hurting a lot. Initially bought for a marathon I have no other choice than to purchase another type of shoes and I'll try alternating it. I would recommend trying them out physically and making sure that they don't push too much in your midfoot, otherwise you'll start feeling in the long term.
Hret fit and nice running but major flaw!
This is a nice shoe. I've had 2 pairs for road running. Comfortable shoe and runs. The outsole is horrible though. There is no rubber over the forefoot of the outsole. I have no idea what topo is thinking. Save money? Save weight? Current shoe is about 200 miles and the foam is worn through. Unfortunately there are no other stability road shoes. If they covered the full out sole with good rubber this would be 5 stars. There is no puncture resistance. One its worn there is no grip (I'm in East Tennessee. Going down hill on wet asphalt with no rubber on the forefoot and the foam worn out is ...not safe and slick)
I like the fit of the shoe. But sole durability is terrible
I use them for walking only on side walks. Maybe 10 miles a week. All of the exposed foam on the bottom wears out. The rubber sole is fine but it is not enough. Where the ball of your foot hits its foam. Like it is planned to wear out. I have not even had these 4 months.

Painful, medial post or support causes sore arc
I reorder an standard width for a wide, which wides only come in this model. The width was great and the overall platform of the shoe was wider in the midfoot; wider than their competitor Altra Running Shoes. However, all of this aside, this is supposed to be a support shoe so if has a firm foam medial post which hurts the arch for me and overall I have pain in my metatarsal area and my heal was sore after a run. If you must have these for support, you'll have to purchase a high cushion insert/insole.