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Asics is one of the best running shoe brands on the planet and one of my favorite ones (if not my favorite). You are looking for a new pair of Asics running shoes, but you have a question that needs an answer: Do Asics run small, big, or true to size?

I am a huge Asics fan, especially when it comes to running sneakers (Asics Cumulus are still my number one running shoe pick year after year), but I also like the running tops, shorts, and socks. Quality is an important requirement when it comes to the Japanese footwear brand.

I have worked as a sales assistant in an Asics store in London for a couple of weeks and worked with Asics shoes for years as a Footwear Manager of a multi-brand sports company. I have served thousands of people with Asics running, tennis, rugby and helped them choose the best shoe size. This means I know what Asics styles customers usually went up or down in shoe size.

Read: Where Are Asics Made?

Asics has many different shoe types, but I decided to focus more on the running styles since they are the most popular ones. Let’s find out the answer to the question: do Asics run big or small?

Do Asics Run Small, Big, Or True To Size?

Do Asics run small or big? Maybe most sneakers run true to size? Asics shoes can run predominantly too small or true to size if you want a quick answer. It’s infrequent for an Asics shoe style to run too big.

Do Asics Run Small?

Asics GT 2000 and NovaBlast can run predominantly small for most runners but also true to size sometimes. Other Asics styles that can run small (but not exclusively) are the Kayanos, Cumulus, Nimbus, GT 1000, Excite 8, and Tennis sneakers. 

Do Asics Run Big?

No Asics shoe style runs predominantly too big. However, some Asics tennis shoes can run too big for some people, alternating between bigger, smaller, or accurate sizes.

Read: Do New Balance Run Big Or Small?

Do Asics Run True To Size?

No Asics shoe style runs predominantly true to size. Some styles that can run true to size (but not exclusively) are the Kayanos, Cumulus, Nimbus, GT 2000, GT 1000, Excite 8, NovaBlast, and Tennis sneakers. 

Asics Sizing Chart & Fit

You can always check the Asics shoe sizing chart to ensure you are buying the correct size (especially if doing it online).

Asics Shoe Size Guide
Sources: Asics

To ensure you buy the correct size of your Asics shoes, you may want to measure your feet.

If you place a paper on the floor with one end of your foot against a wall, you can mark the piece of paper where your toes end with a pen. Then you measure the mark you created on the paper with the end and compare the measurement to the Asics shoe size chart.

That’s how you will get the correct Asics size. But keep reading because you have other elements you need to consider.

How Do Asics Fit?

Many people have the idea that Asics sneakers run too small, so they decide to buy a bigger size without trying the shoes. Most Asics styles can indeed run too small, but they can also run true to size, so it’s important to know what size to choose when shopping for Asics shoes online.

I vary my size on Asics shoes according to the style I buy, and the same will happen with you. I would always advise you to pay attention to the reviews of the shoes you are purchasing (I did that for you if you keep reading) to decide which size will be the best. No shoe brand has one-size-fits-all styles.

Read: Do Puma Shoes Run Big Or Small?

To make your life easier, I have mixed my personal experience selling Asics shoes (including Asics store and multi-brand store) and read reviews on Asics website of specific Asics styles to back up my claims on why I say some shoe styles run too small and others true to size.

Do Asics Gel Kayano 28 Run Small Or Big?

Asics Kayano 28 can run too small or true to size.

The Kayanos are among the most popular Asics styles, especially for runners who need support and stability. I had tried the Kayanos (but not the 28) for curiosity when I worked for Asics because they were so popular and they fit true to size.

However, on online reviews, some runners say their Kayanos are true to size, and others state the same style is too small. Kayanos are also one of the best shoes for overweight men in my opinion.

My Experience With Customers On Asics Kayano 28:

My experience with Kayanos and customers in-store says they can run true to size or too small depending on your needs as a runner. For example, some runners preferred to buy a half size bigger because they wore extra padded socks.

What Reviewers say about Asics Kayano 28:

One runner advised that anyone buying this style choose a size larger than their usual size because the shoes can be too tight or provide a snug fit. Other runners said they purchased the standard shoe size from other running brands, and the shoes fitted true to size.

Do Asics Gel Cumulus 23 Run Small Or Big?

Asics Cumulus 23 can run too small or true to size.

The Cumulus is my favorite Asics style and the one I have bought for the last few years since I am a neutral runner and just need extra cushioning. In my case, they ran too small (I was buying US 10, the wrong shoe size for my feet) in the past, but they run properly to size right now with a US 10,5 (that’s why you should do the gait analysis if you can).

Online reviews also express a balance between the Cumulus being too small or true to size.

My Experience With Customers On Asics Cumulus 23:

It really depended on the customer. Some went for a half a size bigger because they were feeling the shoes too narrow (in case we didn’t have the wide feet in the color they wanted), others a full size bigger because their feet would swell a lot (again, only if we didn’t have the wide feet version). Some were wearing the same size they usually bought on other brands.

What Reviewers say about Asics Cumulus 23:

One runner expressed that he ordered the usual size of running shoes, but the shoes were too small, and he had to go half a size bigger. Other runners stated that this style fits true to size and the shoes are very comfortable and supportive.

Do Asics Gel Nimbus 23 Run Small Or Big?

Asics Nimbus 23 can run too small or true to size.

The Nimbus is a fantastic style, especially if you need a lot of cushioning to protect your knees and ankles since this style absorbs all the impact. I did try the Nimbus, and they did run true to size in my case, but I felt my feet a little bit snug. The extra-wide version was too big, so if I had chosen the Nimbus, I would stick with the US 10,5 since they would get loose after a few runs.

Online reviews have customers saying this style runs true to size or too small. Nimbus is also my number one choice when it comes to the best shoes for retail workers.

My Experience With Customers On Asics Nimbus 23:

Customers in-store usually felt Nimbus was half a size too small, and they would buy a half size bigger (not the wide feet version, because that didn’t work for narrow feet). We did have some customers buying true to their size, but not as much as those purchasing half a size bigger.

What Reviewers say about Asics Nimbus 23:

One customer said the Nimbus ran true to size, and if the shoes feel too broad because you have narrow feet, you must lace all holes. Other customers stated they would have preferred half a size larger since the shoes were a bit tight.

Do Asics GT 2000 10 Run Small Or Big?

Asics GT 2000 usually run too small for most runners and sometimes true to size.

Most online reviews say this style is too small and narrow, and I agree with them. I had to go a half a size bigger, but even when I went for a full size bigger, I would say they fit ok. I don’t have wide feet, but the shoes in my usual size felt too tight.

Read: Can You Wear Training Shoes Casually?

My Experience With Customers On Asics GT 2000:

With the GT 2000, most customers complain that this style felt too narrow in the instep. For some of them, buying the wide version was enough to make the shoes fit better, but others had to go for a half size/full size bigger.

What Reviewers say about Asics GT 2000 10:

One runner said he has average feet (not too narrow or wide), and this style was too tight, so he had to purchase half a size bigger. Another said he ordered the wider version, and the shoes were too narrow on his feet. Some customers said this style was true to size and fitted correctly.

Do Asics GT 1000 10 Run Small Or Big?

Asics GT 1000 can run too small or true to size.

The GT 1000 was also popular in my store in Canary Wharf, London, so that’s the reason why I have tried them. It’s a good shoe if you need stability and don’t want to spend that much money on a pair of Kayanos, but they are built for short distances.

Online reviews are also between the style runs too small or it’s true to size. In my case, the GT 1000 fit true to size.

My Experience With Customers On Asics GT 1000

When customers said this style was too narrow, the wide version would usually fit perfectly, without the need to go for a size bigger. However, some state they were too tight in the insteps and purchased the wide version half a size bigger (or just half size bigger if they had narrow feet).

What Reviewers say about Asics GT 1000 10:

Many runners have reviewed this shoe style as too small and narrow, so they had to purchase half a size or full size bigger. However, some of them said this style ran true to size and fitted flawlessly.

Do Asics Gel Excite 8 Run Small Or Big?

Asics Excite 8 can run too small or true to size.

I never tried this style because it wasn’t the most popular in-store, and I think Asics has better options for neutral sneakers. I would always bring a pair of Cumulus or Nimbus for customers to understand the difference between both styles.

Online reviews say that this style can run too small or true to size, no matter what gender you have chosen to review.

My Experience With Customers On Asics Excite 8:

I remember that customers could go true to size or half a size bigger with this style. Usually, they would pick the wide version if the shoes were too narrow.

What Reviewers say about Asics Excite 8:

One customer expressed how small this style is because he ordered his usual size on running shoes but had to exchange for a half size bigger because they were slightly tight. However, some other customers stated this style fitted perfectly.

Do Asics NovaBlast 2 Run Small Or Big?

Asics NovaBlast usually runs too small for most runners and is sometimes true to size.

Read: How To Stop Shoes From Rubbing The Back Of Your Ankle?

My Experience With Customers On Asics NovaBlast 2:

I didn’t sell this style in-store, so I can’t tell you what customers said. However, in the online reviews, runners said that this style runs too small in most cases and is sometimes true to size.

What Reviewers say about Asics NovaBlast 2:

One consumer said he usually buys a size US 7 on running shoes, but with this style, he had to purchase a size US 8 because they felt uncomfortable due to being tight. However, some expressed that this style fits true to size.

Do Asics Tennis Shoes Run Small Or Big?

Asics Tennis Shoes can run too small, too big, or true to size, depending on the style you buy.

I can’t remember precisely what style of tennis shoes I have tried, but I remember they were true to size in my case.

Read: Difference Between Tennis Shoes and Running Shoes

Online reviews said they can go true to size, too small, and this is the first Asics style that can also go too big for certain people. It all depends on which Asics tennis style you are picking.

My Experience With Customers On Asics Tennis Shoes:

In-store I can’t remember any customers saying the tennis shoes were too big. Usually, they were too small or true to size, depending on the customer’s needs and the shoe style.

What Reviewers say about Asics Tennis Shoes:

One runner said that he usually buys US 8.5 on different Asics shoes, but he had to go half a size smaller in this style because it was too big. Other runners stated that this style could be true to size or too small.

Tips When Buying Asics Shoes

These are the best tips to follow when buying a pair of Asics shoes (or any other shoe brand). These recommendations are based on my personal experience wearing Asics shoes and serving thousands of customers during my six years in the shoe industry.

Ask For A Gait Analysis And Running Assessment

I loved doing gait analysis and running assessments with my customers on Asics to ensure all customers would have their feet mapped and choose the right Asics shoe and size according to their run style.

Read: How To Tell If Shoes Are Too Big?

With a gait analysis, you can understand how much you pronate (how your foot rolls when you run or walk). This is how it works:

  1. X-ray of both of your feet to decide the best size for you.
  2. Running with a neutral pair of shoes for a few minutes on a treadmill recorded by video.
  3. Based on the results from your run, you try the best Asics shoe for your needs.

A gait analysis can ensure you buy the correct Asics shoe size since everyone has a slightly bigger foot (my left foot is slightly bigger than my right one). Unfortunately, I had a few runners buying the wrong shoe size, and after the gait analysis, they felt much more comfortable with the shoe size they should be wearing.

Try The Shoes

If you decide not to do the gait analysis or shop for your Asics shoes online, always ensure you try the shoes you are buying, even if it’s the same brand, style, and size you always bought. Sometimes shoes have a manufacturing problem inside that you or the footwear specialist are unaware of.

Do Asics Run Small Or Big

I always advise anyone buying shoes to try them around the house for a couple of hours to ensure they are the right size and fit (this is very important if you purchase your Asics online). Some Asics styles may not be suitable for your feet’ shape and needs. You can always return the shoes for a different style, size, etc. (always check the refund policy). If you can’t return your Asics and they are too big, learn how to make them smaller to fit better.

Types Of Socks

The type of socks runners wear can influence the way they run and what shoe size they need to buy. It all depends on the materials, the technology, the thickness, the compression, or even the arch and ankle support the socks provide.

The more features your socks have, the less room they may leave inside of your Asics shoes, and that’s why it’s so crucial for you to wear the right socks when buying or trying your Asics sneakers.


Your lifestyle is also crucial, since your feet take a lot of abuse every day, carrying your weight in activities like running, jumping, walking, or just staying on your feet. All these activities can affect if your ankles and feet swell. 

When you run, your feet can expand and contract. Knowing this is essential since you may need half a size bigger to ensure your Asics are not tight.

Medical Conditions

Medical conditions can have a massive impact on how you run and what shoe size you need. For example, suppose you have diabetes, blisters, bunions, plantar fasciitis, high blood pressure, or claw toe. All these conditions can affect whether you need a bigger Asics shoe size or not.

Common Questions About Do Asics Run Small Or Big

These are the most common questions about do Asics run small or big.

Do Asics Run Larger Than Nike?

When it comes to the length size, both Asics and Nike run pretty similarly. Both brands can be more prominent depending on the fit or style you choose.

Do Asics Run Smaller Than Adidas?

Asics tend to run smaller and narrow compared to Adidas, but it all depends on the styles you have picked. For example, an Asics shoe can be too small for me, and an Adidas style can be too big. However, the opposite can happen to you, so it’s difficult to tell since it depends on your foot features and needs.

You can read more about if Adidas shoes run too big or too small here.

How Do Asics Fit Compared To New Balance?

Asics tend to have a more snug fit and lighter than New Balance (at least my own experience states that), but again, it depends on the shoe styles you are picking.

Do Asics Run Narrow Or Wide?

Depending on the Asics style you buy, the sneakers can be narrow, standards, wide, or extra wide. It all depends on your feet, that’s why it’s so essential to try shoes at home for a couple of hours if you buy them online.

Do Asics Stretch Out?

Yes, Asics shoes can stretch out. Any shoes from any brand tend to expand with time after wearing the shoes multiple times (it varies from person to person). However, some materials like polyester, nylon, plastics, and PU leather are less likely to stretch.

Do Asics Shoes Run Small Or Big?

It all depends on the style of Asics you buy, but the Japanese footwear brand tends to run too small or true to size. Asics can also feel a bit narrow for some runners, so the Japanese brand has four different fits to ensure everyone can choose the right one.

When buying a pair of Asics sneakers, my advice is for you to follow the recommendations I provide in this guide since they are based on my experience with thousands of people buying Asics shoes.