adidas vs ASICS Sizing

A black adidas low-top featuring a white midsole and pink stripes down the side vs a white and silver ASICS shoe with an off-white midsole.
Credit: Shoes from adidas and ASICS

A black adidas low-top featuring a white midsole and pink stripes down the side vs a white and silver ASICS shoe with an off-white midsole.
Credit: Shoes from adidas and ASICS

Finding the perfect fit is key when it comes to performance footwear, especially from top sportswear brands like adidas and ASICS. After all, no one wants uncomfortable trainers cramping their style – or their feet! That’s why we’ve put together this comprehensive guide to help you navigate the subtle differences in sizing and width between these two powerhouse brands.

Whether you’re gearing up for your next marathon with some high-performance top running shoes or just on the hunt for sleek, everyday sneakers, our guide will ensure you find that perfect fit with adidas and ASICS shoes.

How should adidas and ASICS shoes fit?

Knowing how your shoes should fit is a vital first step in deciding whether or not your sneakers fit correctly. This is true for all kinds of footwear, not just adidas and ASICS trainers, although adidas and ASICS do provide their own recommendations on how shoes should fit length-wise.

In ASICS' case, the company recommends leaving about a thumb’s width of space between your longest toe and the front of the shoe. For running shoes though, ASICS suggests going half a size larger than the shoe size you usually get to avoid discomfort.

adidas recommends something similar, although suggests you only need about half a thumb’s width of space at the front of your shoe rather than a full thumb's width. adidas also highlights your heel should feel locked in place in your shoes, and a snug fit around the heel and midfoot area is vital for an optimal fit, especially when it comes to running shoes.

A black and white adidas NMD above a blue ASICS running shoe with a white midsole.
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Credit: adidas / ASICS

To that point, the general rule of thumb from Clarks in regards to width is the ball area and metatarsal bone should fit comfortably within the shoe's widest section. This will prevent any inward compression of your foot and allow enough space to accommodate its width.

We appreciate that's a lot of information, but both brands give guidance on how you can measure your feet at home. With a measurement, you can simply use their size charts to figure out what size shoes you need.

adidas and ASICS size comparison

Now, size charts are incredibly handy, but you'll notice when you start looking at a lot of them that the sizes of shoes from different manufacturers simply aren't the same.

A comparison of ASICS and adidas size charts in white, with white logos for each brand on the left.
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Credit: ASICS / adidas

Using the comparison of ASICS and adidas sizing above, you'll notice a US 8.5 shoe from adidas measures 0.6cm smaller than a US 8.5 from ASICS. Okay, that difference is minor, however, it seems to increase as you progress up the sizes. For example, a US 10 from adidas is 0.9cm smaller than a comparable 10 from ASICS.

Despite adidas shoes seemingly being smaller than ASICS footwear, ASICS shoes are actually listed as half a size smaller in the UK across all sizes than adidas shoes, even though they're technically bigger if you look at the length from heel to toe in centimeters.

These differences are a little tricky to remember, so we'd highly recommend comparing your own measurements to the size guide from whichever of adidas or ASICS you're buying from to get the correct size for your feet.

A white ASICS logo above the brand's width chart in white and blue.
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Credit: ASICS

Things get even trickier when it comes to width. As highlighted above, ASICS has codes for when wide or extra wide trainers are needed, but doesn't provide information on exactly how wide each code is in centimeters. The same applies to adidas.

However, this information can be found online. Here is a breakdown of the codes for a Men's US 8 shoe:

  • B - Approx. 8.73cm
  • D - Approx. 9.68cm
  • 2E - Approx. 10.64cm
  • 4E - Approx. 11.59cm

Bear in mind the approximate measurement for each code depends on the length of your shoe. For example, a US 6 and US 12 aren't going to measure the same across, regardless of whether they're standard or wide-fitting. Width options can vary among different shoe manufacturers too, so bear that in mind when it comes to browsing adidas and ASICS' shoe collections.

Final Thoughts

Finding the right fit can make all the difference in comfort, performance, and style when it comes to adidas and ASICS shoes. By understanding the nuances of their sizing and width options, you’ll be better equipped to choose a pair that feels tailor-made for your feet. Whether you’re running a marathon or running errands, taking the time to measure your feet and consult size guides ensures you’ll enjoy every step in your new trainers.