Choosing the right size of your trail running shoes is essential to guarantee the right protection, cushioning, stability and, above all, to reduce the risk of blistering and the formation of black nails in the toes.

How can you easily calculate the perfect size of your trail running shoes without making a mistake? Have a look at the Mini-Guide below.

Mini-Guide for calculating the correct size for your trail running shoes

If you are about to buy your new trail running shoes on the internet, without being able to try them in the store, you may find yourself in difficulty in determining the correct shoe number.

Let’s see how you can find the right size of the new trail running shoes without making a mistake.

Case 1. You already have an old pair of trail running shoes with which you felt comfortable and that did not cause you any problem, but you are about to purchase a different brand.

On the inside of your shoe tongue, in addition to the reference size for the different countries (EU, UK, US), you find the internal length of your shoe expressed in centimeters (CM or more rarely JP). Use the centimeters to find your corresponding shoe number for the new shoe as it is the only comparable parameter.

Case 2. You can’t find the centimeters of your old trail running shoe or you don’t have a pair of running shoes with you?

You can find the right size by measuring the length of your foot. How to do it?

Here are the 5 steps to calculate your foot length.

  1. Place a sheet of paper on the floor with one side flush against a wall.
  2. Then place one foot on top of the paper with your heel against the wall.
  3. Draw a mark at the end of the longest finger, then measure the lenght from the mark to the edge of the paper.
  4. Add 1 or 1.5 centimeters to the measured length (if you run ultra trails we recommend adding 1.5 centimeters because the feet, after many kilometers start swelling).
  5. Choose the size of your new shoes based on the calculated centimeters and the number, by excess, that comes closest.

At this point, you have found the right size and you can proceed with the purchase of your new adventure companion … good training and good races!

Would you like more tips on how to choose trail running shoes? Maybe you may also be interested in:

  • the checklist for the perfect purchase of the trail running shoe, click HERE
  • what is the drop and which is the right one for your trail running shoes, click HERE

Would you like to chat with a TRM Coach? Contact us here TRM Coach


how to buy trail running shoes