adidas Fortarun 4.0 Kids Review: simple, comfy runners that kids can actually live in

I picked up the adidas Fortarun 4.0 Kids (size 5.5 UK, Core Black) for a kid who is not exactly gentle with shoes – running, football in the playground, cycling, and the classic toe-drag on a scooter. I wanted something that looks neutral enough for school, light for running, and that I don’t have to baby. No flashy colours, just a black shoe that can take a beating and still look acceptable.

On paper, these Fortarun 4.0 tick a lot of boxes: Cloudfoam midsole, textile upper, rubber sole, lace-up, and they’re even listed as washable and "waterproof". The Amazon rating is around 4.6/5 with quite a few reviews, so I was expecting a pretty solid everyday shoe, not some high-performance race trainer, just something that gets the job done for school and sports.

After a couple of weeks of daily use, I’d say they do their job quite well, but they’re not perfect. They’re comfortable, light, and easy to wear, but there are a few points that annoyed me: the sizing is a bit on the snug side, breathability is only average, and I’m not fully convinced by the "waterproof" claim in real-life puddles. Still, for a kid’s shoe that’s used for everything, the overall balance is more positive than negative.

If you’re looking for a straightforward black kids’ runner that works for school, PE, and weekend stuff, these are a pretty solid option. If you expect serious trail-level waterproofing or ultra-durable toe protection for hardcore football every day, you might find their limits. I’ll break down what worked and what didn’t in more detail below.

In terms of value for money, these Fortarun 4.0 Kids sit in that mid-range zone: not bargain-basement cheap, but not crazy expensive either, especially considering it’s adidas. You’re paying partly for the brand, but you do get a shoe that’s comfortable, reasonably durable, and versatile enough to be the kid’s main pair for school and casual sports.

What I like for the price is that you get: decent cushioning with Cloudfoam, a proper rubber outsole with good grip, a simple but practical all-black design that works with school dress codes, and the fact that they’re washable. If you compare them to very cheap supermarket trainers, these feel better made and more comfortable. Compared to more expensive kids’ running shoes from big brands, they obviously have fewer fancy features, but for normal use, the difference is not huge.

On the downside, the "waterproof" claim feels a bit optimistic for the price and materials. You’re not getting a true waterproof membrane here, so if you specifically want something for heavy rain and mud, you might end up disappointed and paying again for a proper boot. Also, if your kid destroys shoes quickly at the toe, you might go through these faster than you’d like, which affects the perceived value.

Overall, I’d call the value good but not mind-blowing. If you want one pair that can serve as school shoes, PE shoes, and weekend sneakers, and you like the simple black look, they’re worth the money. If you prefer to have a dedicated sports shoe plus a separate school shoe, you might find better options by splitting the budget across two more specialised pairs.

Design-wise, these Fortarun 4.0 in Core Black x3 are as neutral as it gets. The whole shoe is black: upper, midsole, outsole, laces. The adidas stripes are there but they blend in, so from a distance it just looks like a plain black trainer. For school rules that require dark or black shoes, this is perfect. For kids who love bright colours and patterns, this will feel a bit boring, so it really depends what you’re after.

The shape is a standard low-top running shoe: slightly rounded toe, a bit of volume at the front, and a basic running-style sole pattern. Nothing flashy. On foot, it doesn’t look bulky, which I like. Some kids’ shoes are weirdly chunky; these look more streamlined. My main observation is that the profile is a bit "adult-runnery" which I actually like for older kids/teens, because it doesn’t scream "little kid shoe".

In terms of practical design details, the lace system is basic but works fine. No elastic laces or velcro though, so if the kid can’t tie laces yet, this might be annoying. There’s a small heel tab but it’s not super pronounced; it helps a bit when pulling them on but don’t expect miracles. The toe area has some synthetic reinforcement, but it’s not a full toe bumper, so kids who drag their toes on concrete will eventually wear it down.

Overall, I’d say the design is functional and low-key. Good for school, good if you want one pair to go with any outfit, but not exciting. I personally like this kind of simple look, but if the child wants bright colours or fun details, this model in all-black might feel too plain. From a parent point of view, the all-black colour is practical: dirt and scuffs are less visible, and they still look decent after a rough week.

Comfort is where these Fortarun 4.0 do pretty well. The Cloudfoam midsole gives a soft, cushioned feel underfoot. The kid wearing them immediately said they felt "bouncy" compared to their older, flatter trainers. For walking to school, PE, and running around at break, the cushioning is clearly enough. After a full school day plus some playground time, there were no complaints about sore feet or rubbing, which is usually a good sign.

The fit is listed as regular, but in practice I found them a bit on the snug side, especially in length. If your kid is between sizes or has a wider foot, I’d seriously consider going half a size up. With normal socks, the 5.5 UK was fine but with thicker winter socks it started to feel a bit tight in the toe box. The width is moderate: not super narrow, but definitely not a wide-fit shoe. Once laced properly, the foot feels secure and there’s no heel slippage.

In terms of breathability, they’re okay but not great. The textile upper lets some air through, but because it’s a bit denser (probably to help with the water resistance), feet can get warm if the child is running a lot indoors or on a hot day. After PE, the shoes were warm and slightly damp inside, but not to the point of being soaked with sweat. For autumn/winter as listed, they make sense; for very hot summer days, they’ll feel a bit warm but still usable.

Overall, I’d rate comfort as good for everyday use. Soft cushioning, no obvious pressure points, but watch the sizing and sock thickness. If your kid has very wide or very sensitive feet, you might want to try them on first or look at a more roomy model. For a normal-foot kid, they’re perfectly fine for full days at school and after-school activities.

The shoe uses a textile upper with synthetic overlays, a rubber outsole, and a Cloudfoam midsole. In hand, the upper feels reasonably sturdy for a kids’ shoe, not paper-thin but not super thick either. The textile has a slightly structured weave, which gives it a bit of resistance against scrapes, but it’s still fabric, so if your kid is constantly dragging their toes on asphalt, it will eventually show wear.

Inside, the synthetic lining is smooth and didn’t cause any rubbing issues in our case. No rough seams that I could feel from the inside, which is important for kids who complain quickly about discomfort. The insole is basic but cushioned enough. It’s not some orthopedic thing, just a simple foam insole that works fine for everyday use. Nothing premium here, but nothing that feels cheap either.

The rubber sole is one of the better points: it has a decent thickness and a tread pattern that grips well on normal surfaces like pavement, playground tiles, and indoor floors. On very smooth wet tiles, it can still be a bit slippery, but that’s the case with most sneakers in this category. I didn’t see any weird early peeling of the rubber after a couple of weeks, which is good. The foam midsole is soft and compresses as expected; long-term compression will depend on how heavy and active the kid is.

Overall, I’d call the materials solid mid-range for a kids’ shoe. You’re not getting premium leather or high-tech membranes, but for a textile/synthetic runner, it feels honest. The "waterproof" label is a bit optimistic in my opinion: the upper doesn’t behave like a full waterproof membrane shoe, it’s more like it resists light splashes. For the price point and the adidas branding, the materials are in line with what I expected, but don’t expect miracles in harsh conditions.

Durability is always the big question with kids’ shoes, because they’re basically torture-tested every day. After a couple of weeks of pretty rough use (running, scooter, a bit of football, some dragging on concrete), the outsole and midsole still look really good. The rubber hasn’t worn down in any weird spots, and the Cloudfoam hasn’t compressed in a noticeable way yet. So underfoot, they seem solid so far.

The upper shows some light scuffing at the toe and sides, which is totally normal for black textile shoes. No holes, no seams coming loose, and no peeling of synthetic overlays yet. The toe area has a synthetic reinforcement, but it’s not super thick. If your kid regularly uses their shoes as brakes on a scooter or drags their toes playing football on asphalt, this is where you’ll likely see damage first. It’s not worse than other textile kids’ runners in this price range, but it’s not indestructible either.

I did a quick cleaning test: a gentle hand wash with a soft brush and mild soap. The shoes handled it fine, dried overnight, and kept their shape. The "washable" claim is fair, at least for hand washing. I wouldn’t personally throw them in a hot machine wash all the time, but a gentle cycle in a laundry bag at low temperature should be okay occasionally if you’re careful.

Overall, I’d say durability is pretty solid for a kids’ everyday shoe, as long as your expectations are realistic. They will eventually show wear, especially at the toe, but for normal school and playground use, they feel like they’ll last a season without falling apart. If your kid is extremely hard on shoes, you might want something with a fully reinforced toe cap or a more rugged design, but for average use, these do the job.

In day-to-day use, these Fortarun 4.0 behave like a decent all-rounder. For walking, playing, and light running, the cushioning and grip are absolutely fine. The kid used them for: walking about 20–30 minutes a day, school breaks (lots of running and short sprints), and occasional football on the playground. The shoes handled all of that without any real issue. No slipping on normal surfaces, no complaints about feet hurting after activity.

For running performance, if you’re thinking proper athletics or regular training, they’re okay but not special. They’re more on the soft side, so they feel comfortable but not very "responsive". For kids just doing school PE or the odd fun run, they’re more than enough. If your kid is actually training in a club or competing in running, I’d look at something a bit more performance-oriented with better support and a more structured upper.

On the "waterproof" point, I tested them in light rain and on wet pavement. They kept feet dry in a drizzle and when walking through shallow wet patches. But once you hit bigger puddles or wet grass for a while, water eventually seeps through the upper. So yes, water resistance is there to a degree, but calling them fully waterproof is pushing it. For a typical school day in autumn with some rain, they’re fine. For long walks in heavy rain or muddy fields, not so much.

For indoor floors (school corridors, gym), grip is decent and they don’t leave marks. On very smooth, glossy tiles when wet, they can be a little slippery, but I’ve seen worse. Overall, performance is good enough for mixed use: walking, playground, PE, and casual running. Just don’t expect them to replace a proper trail shoe or a specialised sports shoe if your kid is really into a specific sport.

On the box, this is the adidas Fortarun 4.0 Junior, model number NNT98, size 5.5 UK, colour "Core Black Core Black Core Black". So basically: all black, low-top, lace-up running shoe for kids, unisex. It’s sold as a running shoe, but in reality it’s clearly aimed at everyday use: school, playground, light sports. The product page throws in a bunch of tags like "running", "waterproof", "washable", "autumn/winter", and "casual" which tells you they’re trying to make it a do-it-all shoe.

The upper is textile with synthetic overlays, the sole is rubber, and inside you’ve got a synthetic lining. The midsole uses adidas’ Cloudfoam foam, which is their soft, cushioned stuff you see in a lot of entry to mid-range models. Closure is classic laces, no straps, no BOA system, nothing fancy. It’s listed as a low-top with ankle height shaft, round toe, no heel, and a regular fit. In practice it feels like a fairly standard kids’ runner, not too narrow, not super wide either.

One thing that’s a bit confusing: the specs mention waterproof and also that they’re washable. So adidas seems to expect these to get dirty and be thrown in the wash, which is realistic for kids. But "waterproof" here is clearly not meant in the same way as a hiking boot with a membrane. It’s more like: they handle light rain and wet pavement reasonably well, but they’re not magic in deep puddles. I’ll get back to that in the performance/durability part.

Overall, the presentation is that of a simple, all-purpose kids’ shoe with comfort and practicality as the main promise. No huge tech story, no crazy design, just a black sneaker that’s supposed to do everything fairly well. And that’s more or less what you get in reality, with a few caveats.