Carv Sizing Guide

October 1, 2023

6 min read

Carv comes in three sizes to ensure sensor coverage of almost every boot size. This is selected at checkout based on your shoe size:

  • Size D
  • Size E
  • Size F

To find out your Carv size, you need to select your shoe size at checkout.

Ensuring Carv doesn't interfere with boot fit

Ski boots are the most critical part of your ski gear. A good tight fit is essential to give you an optimal feel for great skiing performance and comfort on the slopes. So when we set out to design a pressure-sensing boot insert, the core challenge facing us was balancing being able to take accurate measurements without negatively impacting an already tight boot fit.

How it fits into the boot

Most of our skiers have a custom-fitting boot, and usually a custom orthotic as well. By designing a system that fits under the liner we designed Carv to be compatible with:

  • heel lifts
  • custom insoles
  • custom fitted boots
  • boot warmers.

Because Carv goes under the liner, on top of the plastic boot board, it doesn't interfere with these kinds of adjustments. Heel lifts can be placed on top of the unit if those are used.

Carv fits under the liner

Sensor Placement and wires

We have the largest dataset on the pressures and forces inside a ski boot of anyone on the planet (we're pretty sure we do at least). So when we design Carv, we use that data to ensure we're routing the cables, and the sensors through areas of the foot that have the least impact on fit - reducing the chance of any boot-fit pains.

We've spent years studying where to route the cables and what materials to use to get a high performance sensor with the minimum disruption on your fit possible.

How thick/thin is it?

Carv is 3mm thick. This level of thickness is barely noticeable in almost every leisure skier's boot. 99% of Carv skiers do not have any issues and we get very few returns for boot fit issues. We understand the risk of modifying your boot setup with any new addition, that's why we offer a 100-day boot fit guarantee so you can try Carv in your set up. Simply return it for a full refund (membership and device) if there are issues.

If you do have any issues, rest assured that in most cases you'll be able to make small adjustments at a boot fitter to get it fitting perfectly.

However, even our pro ambassador Ted Ligety, 5x world champion racer skis on Carv without any boot mods.

Still not sure?

We've uploaded our database of the boots that Carv is running in so you can explore to see if your own boots are represented.

Want to double check your size? Check your Mondopoint

If you want to double check the sizing before you buy, you can always compare your boot size - known as the Mondopoint size of your ski boot with our table below.

This number will be in the 20s or 30s and goes up in half sizes. 26.5 is an example of a Mondopoint size. On most ski boots, the Mondopoint size is found on the shell at the base of the boot. Here's a typical location of the Mondopoint size:

Once you have found your Mondopoint size, you can use the table below to find your Carv size, shown in the left-hand column. We have also included the typical corresponding shoe sizes.

If you are on the border of two sizes, we recommend that you choose the size below.

Select your size

What if I'm in between sizes?

If your boots are on the boundary between two Carv sizes, choose the smaller size.

Skiers do not exert pressure at the very front or very back of the boot so a slightly smaller size will not affect your skiing data.

Secure the insert centrally in your boot so that there is equal amount of space at the front and back of the boot.

Carv sizing template

If you remain unsure as to which size you require, you can use the templates linked below to see which best fits your ski boot.

Letterhead template
A4 template

Boot Fit Guarantee

When you buy Carv, you are protected by our Boot Fit Guarantee. If you don't find your perfect fit, simply exchange Carv for a different size or return it for a full refund within 100 days.

Common questions:

Can I use Carv with Apex/Dahu boots?

We do not guarantee compatibility with Apex or Dahu boots however, we have had multiple accounts of customers successfully using Carv in these boots.
Please see our full article on boot compatibility here.

Will these inserts be uncomfortable or require me to get my boots refitted?

99% of our customers are happy with their Carv fit - even pros like 2x Gold Olympic Champion, Ted Ligety, ski with Carv without boot mods. Because it fits under the liner, there is padding to accommodate the 3mm volume. If you do have a pinch, a boot fitter can rectify issues. If not, you are protected by our boot fit guarantee.

Can I use Carv with custom foot beds/heel lifts?

Yes! Carv is installed between the liner and the shell of your ski boots, whereas custom orthotic foot beds and heel lifts sit inside the liner.
Carv is therefore compatible with custom foot beds and heel lifts. If you have canting insoles or heel lifts, please make sure you put your Carv inserts underneath these.

Does Carv work with custom insoles, boot warmers or heel lifts?

Yes. Carv goes under the liner - on top of the boot board. This means that heel lifts, custom insoles (e.g. Surefoot), and boot warmers are not affected and are compatible with Carv. You can use them both at the same time.

Contact us


The fastest way for us to help you is through the Carv App. From here we can help you with any questions or issues you have by reviewing your session data and providing troubleshooting steps directly in the App.


Alternatively, get in touch with us via Live Chat below.

Our working hours (9am - 1:30pm ET, or 9:30am-5:30pm BST).


For purchase or product assistance, please contact us through the app as it allows us to support you more efficiently.

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