Shoe size conversion – Why my shoes don’t fit? (Part 10)

The shoe size conversion, from the foot to shoe size, requires the foot length as well the foot width.

In the previous post “Why my shoes don’t fit? (Foot Measurement)”, I’ve shown you a different way of calculating the length of your feet. We are measuring the distance from heel to the inside joint, calculating than our foot length-length and compare this with the length of the shoe last, again the length from heel to joint.

As I have mentioned it before, we should start thinking of using or wearing a shoe size, instead of having a shoe size.

Shoe manufacturers are providing us also with the information of the shoe width. It’s most of the times not stamped in the shoe itself, but usually, we can find this information on the shoe box itself or in the online description. Qualified stuff in the stores should have this information as well for you.

The shoe width has to be measured around the joints. With the measurements of the shoe width and length of our feet, we can complete the shoe size conversion.

Measure your feet width with a measurement tape or if you don’t have one, simply cut a 10 mm stripe from a normal printing paper. Cut horizontal along at the edge of the paper, which gives you a stripe of approximate 300 mm length.

Put your tape under your foot, so that it’s along with your joint-line. (See picture above). Remember, the joint-line is from the inside of the big bone to the prominent bone on the outside of your foot, which is actually the widest part of your foot. Now you just wrap the tape over the joints and where the two ends of your tape are overlapping, mark it with a pencil. Don’t pull the paper tape too strong, put it firmly, you should feel the tape around your foot – too loose is not correct either. Think how you would like to fit your shoe around the joints – neither loose or tight.

Important: If you’re doing the foot measurement yourself, you need either to stand in a relaxed position or sit on a chair and keep the body weight at the heel. Otherwise, you would put too much pressure on the toes and your joints would expand too much, which would not give us the appropriate measurement.

You can try it out for yourself and see the difference: pressure on/pressure off the foot. Sometimes the difference is more than 10 mm with weight on the foot.

Note down the measurement and start with the other foot. Now compare these two measurements. Usually, there will be some small difference of 2-3 mm. If your differences are too big, like more than 5 mm, check your measurements one more time. Anyhow, I would suggest doing the measurement twice. Like the old carpenters always said: “Measure twice, cut once”.

In case you still find a big difference between both feet, then you have the same problem like me: we are having two different width fittings and this is certainly the course why your shoes don’t fit. In this case, you have no other choice; always fit your shoes for the wider foot and adjust the slimmer foot in the shoe with thicker or two pairs of socks. You could also ask your next door cobbler to add some extra layer of foam to the shoe. The best choice, of course, would be to get your shoes made to order, but still, you can’t get all your shoes done like that, you need to find solutions to adjust this issue.

After having determined our foot width, we can look into the shoe-size-width tables. You can click on the links to check your shoe width, for European-Sizes, UK-Sizes or US-Sizes.

Now let’s assume for example, that the width of our foot would be 255 mm. We are looking in the conversion tables and getting following results.

UK-Width: “G” and US-Width: “D”

With the help of our calculated shoe-size, we have completed now the shoe size conversion. In this example we have detected following shoe sizes and shoe widths:

For the UK: Size 10/G and the US: 10.5/D

Try this system for your shoe size conversion. See how it works out for you – as you know by now, there is nothing fixed – everything is possible as long the shoe fits. For moccasins and slippers, I like to reduce the shoe width for myself by one size down and try to get a shoe size up.
Sometimes you will figure out, that the calculated shoe size conversion works well only for certain shoe brands. However, certainly some trial and error e is required, but once you’ll get the idea, this way is certainly the best shoe size conversion for your feet.

But most important:  You have gained new ideas about your feet!

I like to mention here, that for open types of footwear, like sandals or peep toes, I would not use the calculated shoe size conversion, instead I would first try with my actual foot length, because sandal lasts are different build than shoe lasts, but again, nothing is fixed, you’ll need to try it out for yourself.

Finally, some remarks about shoe size conversion and foot measurements. For a complete foot measurement, there are more important measurement points required than just the foot length and the width of the joints. Unfortunately, the shoe industry is not disclosing these measurements and that’s why we don’t mention them it in this article series – there are of no use for industrial shoes.

This is the end of the article series “Why my shoes don’t fit?” and we hope, that you have gained some valid information and enjoyed the reading. You can also download the entire series as

free ebook-shoe- guide with more measurement instructions.

Best wishes,

Andre Gerdes ( the shoe size conversion-cobbler)