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Do Asics Run Small Or Big? From A Shoe Expert

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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.

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.

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 Amazon and 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 Asics and Amazon 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 Amazon Reviewers say about Asics Kayano 28:

“Great quality, must have runners but runs a little small, so I had to return.”
“Birthday present, fit perfectly true to size and arrived when expected.”
“My personal advice to anyone would be to buy a size bigger than your normal size.”
“Fits true to size. I highly recommend these.”
“I ordered my normal size, but were too short and had to return and reorder a size larger.”

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).

Amazon and Asics 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 Amazon Reviewers say about Asics Cumulus 23:

“I ordered the same size as the others. When they came in, the size on the shoe said the correct size, but we’re way too small!”
“They do not run true to size. They run small – consistent with other Asics styles.”
“Very comfortable shoes, but I had to return for half a size bigger.”
“Fit true to size. Comfortable & supportive.”
“Perfect fit true to size. This is a very comfortable shoe.”
“True to size, great arch support. Will purchase again!”

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.

Both Amazon and Asics reviews have customers saying this style runs true to size or too small. Nimbus are 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 Amazon Reviewers say about Asics Nimbus 23:

“Perfect fit, true to size.”
“Order 1/2 size up. They run small.”
“I should have gotten a half size larger.”
“They were true to size. If you have a narrow foot, lace all holes.”
“These run at least a half size too small. I am usually an 8.5 wide. I had to step up to a 9 wide for the fitment.”
“Great shoes! May need to select half a size bigger.”

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 reviews on Amazon and Asics websites 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 Amazon Reviewers say about Asics GT 2000 10:

“My feet are average, and these are just too tight and uncomfortable.”
“Shoes too small – too short.”
“I didn’t purchase them too small or too big. The fit was perfect.
“I usually wear a size 11,5, but I had to move up to 12 because 11,5 was too small.”
“These run really small. And are narrow even if you order them wide.”
“Feel great, but they are a wee bit small.”

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.

Asics and Amazon 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 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 Amazon Reviewers say about Asics GT 1000 10:

“Perfect fit, true to size.”
“It fits perfectly. As i wear wide size and i order 9.5 extra wide and its fit perfectly.”
“They run too small and too narrow.”
“True to size…shoelaces too short.”
“The fit is just perfect and ultra-comfortable.”
“Too small…at least half, possibly full size.”
“They ran very small. I couldn’t even get my foot in it.”

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.

The Amazon and Asics 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 Amazon Reviewers say about Asics Excite 8:

“They are true to their size.”
“True to size and width.”
“Size up! These sneakers run small and narrow. I am a true 7.5 in any shoe, but I went up a size after reading the reviews. I’m so glad I did!”
“Typically a size 8, but I find ASICS to be a bit tight, and 8.5 is perfect.”
“Definitely order up a size. They run small. I am normally an 8.5, and I ordered 9, and it fits well!”
“Fits perfectly true to size.”

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 Amazon and Asics reviews, runners said that this style runs too small in most cases and is sometimes true to size.

What Amazon Reviewers say about Asics NovaBlast 2:

“True to size, bouncy, looks cool.”
“I usually wear a 9 and these fit me just fine.”
“I normally wear a size 6 in most of my shoes. So I had to buy a size 7.”
“I purchased my normal size, and when I tried them on, they were smaller than average. Not true to size.”
“I do think they run small. I normally wear a 9 in shoes but ordered a 9.5 in my first pair. They are ok, but I just ordered a size 10 for my next pair.”

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

Asics and Amazon reviews say 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 Amazon Reviewers say about Asics Tennis Shoes:

“After using them for a while, my recommendation is to buy your true size. I bought half a size more, they stretched a little, and now they run big for me.”
“Very comfortable, true to the size.”
“I ordered my regular size, but this pair of ASICS was slightly smaller.”
“They run a little small.”
“Is larger than actual size. I have 6 pairs of Asics, size 5 that fit perfectly, and these were big.”
“Order my size, but the shoe is a size too big.”

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.