How to Find Your Chaco Size

This post may contain affiliate links that help me continue to grow Shelemah. For full affiliate disclosure click here.

How to find your Chaco size

Chacos are well known for their adjustable straps and bright colors. The sandals only come in whole sizes, leading to some confusion for those that typically wear a half size. Typically the advice is, if you wear a half size to go down to the next whole size for Chacos. For many people that simple rule of sizing will get them in the right Chaco size. However sizing Chacos is much more than just going down to a whole size. Chacos are sized by the heel-to-ball measurement instead of overall foot length like most shoes.

Shelemah chaco feetOur feet are the foundation of our entire bodies. No amount of chiropractic care, yoga, organic food, supplements, or other health practices can make up for an unstable foundation. Proper fitting footwear and a well supported arch  are the building blocks of whole body health so getting the right size Chacos is super important.

When I was in undegrad and grad school, I worked as a footwear specialist at REI.  While it’s been several years now since I donned a green vest and had the nickname “Chaco Queen”, my passion for Chaco sandals and properly fitting footwear has never left me. So without your foot in front of me to measure, here is my best online  attempt to show you how to find your Chaco size.

How to Find Your Chaco Size

Measuring with a Brannock Device

heel to ball measurement

As you can see in this lovely photo of my foot. My overall foot length is just a smidge over 8.5 and my heel to ball measurement (right arch length on the Brannock device) is just a smidge under 8.5. My foot width is a solid B, narrow to regular width.

What all this translates to with Chacos is that the typical “go down to the nearest whole size” recommendation is correct for me. So I wear a size 8 in Chacos even though I typically wear an 8.5 in other shoes.

Any well trained footwear staff should be able to measure all this for you, but you can also measure yourself. The Brannock device has been around for decades as the measuring standard for footwear and is simple to learn to use.


Your Toes Will Fit

When I first bought a pair of Chacos, and knew none of this important information, I got a size 9 because I didn’t want my toes to hang off the edge of the shoe. Unfortunately, because a 9 arch length is too long for me that first pair of Chacos was never comfortable and would hurt my arch and heel after wearing them for a little while.

size 9 chacos

Size 9 with a good half inch of space between my toes and the edge of the shoe.

Size 7 chacos

Size 7, clearly too small and my toes are hanging off the edge.

size 8 chacos

Size 8, perfect fit.








Despite my initial fear that 8’s wouldn’t give my toes enough room, they fit perfectly and I have never had an issue with hitting my toes while wearing my Chacos. If you’ve ever seen someone wearing Chacos and thought they looked big and clunky they probably were wearing too large a size. Properly fitting Chacos should hug your foot and not add bulk.


Luvseat Orthopedic Footbed

Chacos are made with their patented Luvseat orthopedic footbed which is certified by the American Podiatric Medical Association. What that means is that the APMA has found the footbed to promote good foot health. When I worked at REI we had some local podiatrists that would send people to use to get fitted for Chacos because they help alleviate plantar fasciitis as well as some other common foot issues.

The reason heel to ball measurement is so important for Chacos is the way their orthopedic footbed cups the heel and supports the arch. Your foot has 26 bones and 33 joints. A few of those joints are especially important to support so that your foot is stable, preventing pronation or supination.

Subtalar Joint

The highest point of the arch on a Chaco footbed should be supporting the subtalar joint. A good way to tell if it is hitting in the right place is to imagine a line going straight through your foot from the front of your ankle. The reason the size 9’s hurt my feet is the arch of the footbed was hitting too  far back on my foot. The support was behind the subtalar joint instead of right under it.

size 8 subtalar

Size 8 Chacos showing where subtalar joint is supported

Size 9 Chacos showing how support is too far behind subtalar joint. Not providing proper support.








Heel Cup

Our heels have a nice pad of fat that provides natural cushion. The Chaco Luvseat  footbed cups your heel so that cushion is maximized for all day comfort. This is why getting the proper width Chacos is so important. If the shoes are too wide the heel is not cupped, and the cushion is diminished. Your heel can also slide around side to side leading to decreased stability. If the shoe is too narrow not only will the heel be uncomfortable, but the arch will hit in the wrong place and the straps will be too tight no matter how much you adjust them.

Another reason you may look at trying a wide Chaco size is if your overall foot length and your heel to ball differ by a whole size and the heel to ball is smaller. The wide size Chacos are a little bit longer than the mediums without changing the arch length. So if you are a size 8 heel to ball and size 9 over all foot length, an 8 wide may actually give you the best fit. Just be sure that your heel is not loose and sliding around in the wide.

Chaco sizes are marked on the back of the heel of each shoe. A dot means it is the regular width, a dash means it is a wide. The M or W by the size number stands for Men’s and Women’s. When Chaco’s first came out they had medium and narrow as their widths. When they changed over to medium and wide they didn’t change the size run, they just changed the labels. So even if you do not typically wear a wide shoe, you may be a wide in Chacos.

chacos size 8 wide

Size 8 wide, see all that extra room on either side of my heel.

chacos size 8 regular

Size 8 regular, perfectly snug fit.








Ajustable Straps

how to adjust chacos

The straps on Chacos are totally adjustable, which enables a perfect custom fit. Even with adjustable straps though, it is still important to get the right size so that the straps hit your foot in the right places. There are tons of great resources out there showing you exactly how to adjust Chacos. Here are my tips for adjusting the straps:

  • Use fabric softener to loosen up a stuck strap, put a little at the base of the strap and floss back and forth till it loosens up.
  • Readjust straps after the first two weeks of wearing them to get the perfect fit
  • Loose is better, there’s no need to get them super tight, just tight enough to stay put it is perfect
  • The heel strap doesn’t adjust. But if you have the right size and the straps adjusted well the heel strap will fit well. It doesn’t need to be super tight, it’s there as a back-stop to keep your foot from sliding off
  • Stay away from sand! The quickest way to ruin a pair of Chacos is to get sand inside the footbed with the straps. The sand rubs at the straps until it cuts straight through them.

[cp_modal display=”inline” id=”cp_id_88e13″][/cp_modal]

This post was not sponsored by anyone. As much as I love REI and Chaco and am sure they love me too, they did not ask me to write this post and have not compensated me in any way.

How to find your chaco size

Related Products:

22 Responses to “How to Find Your Chaco Size

  • My Chacos hurt my heels so much! I love them but can only commit to about half a day in them. I think I should have gone with the wide width. Thanks for the measuring tips.

    • Yep, sounds like a size issue for sure. They shouldn’t hurt as the day goes on, they should feel more comfy.

  • Courtney
    7 months ago

    Thank you! This was super helpful.

  • Catalina
    7 months ago

    Thank you so much for this! I decided to size down and go with the 6 rather than 7. I usually wear a 6.5 and my worry was that my toes wouldn’t have enough space or would hang off the edge. I was having trouble finding a proper explanation as to why sizing down would be better and you did a great job of doing so in writing and through pictures!
    Thank you Chaco Queen

  • Michelle
    7 months ago

    I wear an 8 1/2 too so I went with a size 8 pair of chacos. Unfortunately they are too small. It was hard to get my feet into them and the strap had only about an inch hanging off. Should there be more strap hanging down? I know too much strap is undesirable but I just feel like there is barely any strap leftover. The buckle also sits more towards the inside of my foot when I normally see it sitting towards the outside of people’s foot on pictures. I really want to go with the right size. Would you suggest I exchange for a size 9?

    • Hi Michelle, it’s hard to say without actually seeing them on your feet, but it sounds like you may want to try an 8 wide. A 9 nine might the right size but that would all depend on your heel to ball measurement.

  • I just bought my first pair and I usually wear 8.5-9 so I went with a 9. Two different stores said the 9 was the right size. They feel like a dream on my right foot but my left foot the arch supports is putting a lot of pressure on my foot. I am wearing them around the house to see if they will feel better. My back hurts less in them but not sure how long I can keep them on. The arch just feels like it sits to far forward on my left foot. I tried a 8 on in the store and it also had pressure and my toe was way to close to edge for me.

    • Sounds like an 8 or an 8 wide may be the way to go. The arch hitting too far forward is the classic “too big” feeling. I promise your toes will fit 😉 When you ask a store which size is correct be sure to ask them why. Unfortunately many footwear department employees are not trained on how to size Chacos properly. Did they measure your heel to ball measurement like I describe?

  • I just bought an eight (I typically wear an 8.5) and my heel is slightly hanging over the back, but I have plenty of space in the front by my toes. It feels comfy but I think with the heel hanging off slightly they are too small. Thoughts? Wondering if I should have gotten a 9.

    • Hi Brooke, it sounds like you may need to adjust the straps or try an 8 wide. Did you have the store measure your heel to ball measurement when you got them?

  • I bought an 8M online, I normally wear an 8 1/2. I don’t have access to a Braddock device to measure my arch. its hard to put my foot in it feels like there isn’t enough straps. I ordered a limited edition design that the only make in the medium wide. is there another way to measure heel to ball?

    • Hi Lauren, any shoe store will have a brannock device to measure your heel to ball even if they don’t sell chacos. It’s hard to make sizing recommendations without seeing them on your feet or knowing your measurements.

  • Elizabeth
    5 months ago

    YAY! I love Chacos!! I wear a size 5 wide or 6 regular. They both fit great and I can walk forever in them. The 5 wide are probably the best fit. I seriously wear them all the time!! hahah.

  • Hello I measured the foot with a meter and measures 25 cm and a little more 25.2 or 25.3 and I asked for an 8 because I wear an 8 and my foot is narrow, although my previous sandals of another brand ( ECCO) are an 8 butmore longer than chacos.

    The right foot is perfect, there is more stripe than left, but in the left foot the bow that does not hit well, hits closer to the fingers than the heel … In both feet the measurement of the back heel is to the limit. I do not know if it will be my correct measurement or it is that I have a bow of a different foot. But I’m afraid to ask 9 because my foot is tight

    • Hi Sandra, unfortunately I don’t know if that would be the right size either. I would seek out an REI or other well trained footwear department and ask them to measure you with a Brannock device as I mention in the post.

  • THANK YOU!!!! Thank you so much for taking the time and effort to write this article!! I am so appreciative!! Just got my first pair and I have been debating for hours if they are the right size, and they are =) you really helped me a lot thanks again!!

  • My arches flatten when I stand and walk, so my arches end up slopping over the edge of the footbed in Chacos. What would you recommend? Maybe my feet aren’t meant for Chacos?

    • Hi Katie, it sounds like you may not have found the right size Chacos yet. I would recommend going to an REI and getting properly sized for them. Chacos that fit well can actually help improve your arch health.

  • Erin day
    2 weeks ago

    I want to buy another pair, but not sure if my current size is wide or not. The back of the shoe says w9, does that mean wide?

    • Hi Erin, the W on a Chaco stands for Women’s (M for Men’s) Wide or regular is marked by a dot or dash on the outside of the W9 so a wide would be -W9- and a regular would be .W9.

Join the Conversation