One of the most common queries among runners and shoe geeks is about running shoe size comparison between brands. We interacted with a sheer number of shoe fans and read through numerous reviews of people who actually tested tons of running shoes from different brands including Nike, Adidas, New Balance, Hoka, and Saucony alongside others.
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Running Shoe Size Overview
Those who wear loads of different shoes can attest that they’re often subjected to variation in sizes, between each manufacturer as well as the discrepancies within their sizing guide. Note that some running shoes tend to run a little short, some a little long, some very wide, and some very narrow.
Most people nowadays opt to purchase their shoes online, which is more convenient considering that they can be delivered straight to your door. While buying items online is associated with some sort of risk, you don’t want to open up your fresh new running shoebox, lace them up only to find them to be the wrong size.
About measuring, one problem that constantly perplexes runners is the fact that most of us have got one foot slightly different than the other. And there’s never that option like ordering a left in a 10 and a right shoe in a 10.5. Shoe manufacturers just don’t offer that option and we’d be lucky to have them around.
If you measure both of your feet using a few different methods, most likely all of them will come to the same conclusion that one foot is slightly longer than the other. This makes sense and you might feel that one foot doesn’t have quite as much room as the other. The trivial difference might not feel rather uncomfortable but can bring about substantial variance in running shoes.
Nike Running shoe Size Guide
We’re going to discuss various manufacturers’ sizing guides to help get an idea for the difference that there exists. Starting with Nike, we’ve got the Alpha Fly, which is a fairly popular model on the market. Checking on their size guide online, we found Nike size 11 UK to be 11.3 inches (28.8 centimeters) but looking at any Nike shoebox, you’ll realize that there’s a slightly different thing.
First up, the Alpha Fly seems a little more generous in terms of size- just a little bit longer such that you’ll hardly have problems during the performance. It fits great on foot and has a beautiful pillow-like feeling with some sort of bouncy feel.
The toe box has a really forgiving fit and we think going true to size could be a spot on with the Alpha Fly. We would definitely suggest that if you’re planning on buying this, you’d be better going true to size and not going up or anything like that.
With the Hakone Edition, the size 11.5 in the Nike Next% Hakone Edition tends to fit true to size in comparison to size 11 in the green version of the model. You’re bound to notice the extra length in the toe box on this shoe as it’s more comfortable, even for little toes. It’s just a few millimeters between both versions but that can actually make all the difference.
Pegasus & Turbo
The Pegasus & Turbo may seem somehow less prevalent in different models like the Pegasus 35, the 36, and the 37, but the shoes fit just fine overall. Even the Pegasus Turbo 2 is very much likely to fit true to size. You’d possibly consider going a half size down with the Pegasus Turbo, and they’re still will be ample room in the toe box. Besides, you can read on how to measure your feet correctly on Nike’s Website. Now let’s turn our focus onto Adidas:
Adidas Running shoe Size Guide
Adidas shoe size guide provides exactly the same way to measure your feet that Nike has- though the results aren’t quite the same. Adidas usually recommends a size 13 for 30.2 centimeters (11.8″) heel-to-toe length.
You can get a 13.5 and still be ok, but the downside to Adidas is that they don’t offer a 13.5 in most of their performance shoes including the Adios 5, the Boston 9, and the SL 20.
With a UK size 11, Adidas states something notably different from Nike. They provide a 28.4 centimeters (which is actually 11.18) length on a size 11.
That means the whole 4 mm difference unless perhaps you consider other measurements that are on the toe box. If you’re size 11, for instance, you might want to opt for 11.5 in Adidas shoes as it provides a bit more room. Adidas 11 might feel just way too tight.
With the Takumi Sen, keep in mind that this is a relatively tight race shoe. That means you can go up half a size and still find it spot on. The shoes, however, always seem a little narrower, probably because of the last they’re using.
Checking on the company’s website, their 11.5 comes in at 28.8 centimeters lengthy (11.3 inches), which is also comparable to Nike in a UK 11. Adidas sizing Guide also states that a UK 11.5 is the same equivalent as a US size 12. That means you might need to size up half a size if you’re going for an Adidas shoe.
With the UltraBoost 4, most people tend to go up a half size. So be sure to check through the sizes and have both feet measured too.
The Boston claimed to run true to size, but they are much tighter and you might feel much more comfortable in these. While Boston for everyone, they’re often preferred because they come with a narrow design, which is a bit of a trade-off.
If you’re considering a shoe in Adidas and Nike and pick just what is your true size, it may not actually be the same for both brands. So, read through the charts and be sure to get the right length for you. Now the New Balance:
The New Balance
We think the New Balance found the optimal point between sizing issues and other running shoes. On their website, the UK size 11 is quoted as 29.5 centimeters (which is 11.6 inches).
The Fuel Cell Rebel, for instance, fits really snug in a size 11, meaning you might want to go up half a size. We would suggest being a little bit careful with the New Balance sizing as they seem to run a little short.
With the Beacon & 1080, however, some reported that they went true to size and the shoes still fit just fine. But you can go half a size up in the New Balance 1080 V10 for more ample room.
Overall, it’s safe to say that New Balance Shoes generally do run a little bit snug or rather a little bit short. Luckily, New Balance does offer several different width fittings. But how about Asics?
Asics Running Shoes Size Guide
Asics is a bit different. For most people, Asics shoes are generally spot-on, especially in terms of UK size. Checking on the company website, Asics quotes size 11 at 29.5 centimeters (11.6 inches) and 11.5 at 30 centimeters (11.8 inches. This can pose confusion because the sizes are just all different.
Based on reviews, the Evo Ride, Glide Ride, and the Nova Blast all seem to be spot-on for many in a UK size 11. You’ll hardly have any hill slippage or such in Asics because the uppers on their models are designed to hug your feet like a glove.
On the Asics site, we found a similar diagram of how to measure the length of your feet. One difference about Asics is that the centimeters sizes they put on their chart mostly refer to the length of your feet and not the length of the insole.
You can have a 12 for the Meta Racer and Roablast and 13 in a Nova Blast and still find them equally roomy. We suggest being careful with Asics as their sizing does appear a little longer than other brands.
You can comfortably get away with the 12 in Asics, a 13 in Nike and a 13.5 in Adidas. When we compare the side of the insole by side, they appear to be pretty much the same, meaning that Nike 13 is equivalent to an Asics 12.
We checked the shoebox of RoadBlast in the UK 12 and found that it actually shows 30.5 centimeters (12 inches) as per their size chart. Now to Hoka:
Hoka Running Shoes Size Guide
We found Hoka to be similar to Asics in terms of sizing. They explain how to measure your feet in a similar way to Nike, Asics, and Adidas.
The Hoka Rincon and Carbon X, for instance, feel quite narrow and don’t have that much room in the toe box. Hoka size 30.2 (11.8) falls between a UK 12.5 and UK 13, but the 12.5 fits pretty well.
At UK 12.5, the Rincon Original seems to run quite large because it comes with an almost full thumb width. On the flip side, it’s hard to measure the insoles of a Rincon because they’re glued. Thus the centimeter size may be slightly inaccurate especially with glued insoles.
Saucony size chart likewise seems to provide just a fine fit for most people’s preferences. You’re not likely to find a centimeter size on their website, but you can extrapolate based on what they say on the box. Overall, Saucony and Nike Sizing are exactly the same and very much relatable.
While Brooks doesn’t actually give an actual centimeter of your specific foot size, the size guide provided on their website seems very much comparable to Nike. But the good news is that these shoes seem to be just fine for most people.
The Brooks 13, for instance, is actually 12.5 inch (32 centimeters). We think Nike and Brooks’ sizing is almost the same, especially after comparing reviews from both sides.
The Bottom Line
Chances are you’ve seen a lot of running shoe stores actually recommending that you go up a half size when buying running shoes. While you can’t entirely be sure of the reason or advantage behind their suggestions, it’s always best that you try a shoe and see how it feels.
We recommend going up half a size only if the shoes in question are too tight for you. Best running shoes should be snug; not too loose and not too tight either. You want a pair of running shoes that can give your feet the much-needed room when it’s splayed a little during performances.
All things considered, we think the most reliable way to get the right running shoes for your feet is by actually wearing them. Work out what size shoe is the most suitable for your feet. Measure the insole and check exactly how long that is and then use that as a benchmark to compare with other models from other brands.
Of course, the length of the insole isn’t actually the full picture because it’s likely to be affected by how well it sits in the shoe, the amount of padding and shoe tight the toe box fit. A good example of such a case is the Adidas Boston 6 and Boston 9. Both are said to fit UK 12.5, but with actual measurements, the Boston 6 is significantly shorter than the Boston 9.
Another thing worth mentioning is that generally with running shoes, you want to feel more room than you’d do in your regular shoes, mainly because your feet will expand. So as you’ve already figured out, it’s more of a discrepancy between the different models and their manufacturers.
We haven’t covered all brands but we’re positive that you can easily determine the length of your feet and what shoe is ideal for you. In the end, everybody’s different.