Size Guide: Find Your Perfect Fit
Choosing the right size for your Formthotics is essential to achieving optimal support and comfort. Our size guide provides a clear breakdown for our Standard (Adult), Youth, and Junior ranges, making it easy to find the perfect fit based on the foot size and age range.
Adult range
Size
  | XXS  | XS  | S  | M  | L  | XL  | XXL  | XXXL*  | 
|---|---|---|---|---|---|---|---|---|
UK  | 2.5  | 3 - 4.5  | 5 - 6.5  | 7 - 8  | 8.5 - 9.5  | 10 - 11.5  | 12 - 14  | 15 - 16  | 
Euro  | 35  | 35.5 - 37.5  | 38 - 40  | 40.5 - 42  | 42.5 - 44  | 44.5 - 46.5  | 47 - 50  | 51 - 53  | 
US (Women)  | 4 - 5  | 5.5 - 7  | 7.5 - 9  | 9.5 - 10.5  | 11 - 12  | —  | —  | —  | 
US (Men)  | 4 - 5  | 5.5 - 6  | 6.5 - 7.5  | 8 - 9  | 9.5 - 10.5  | 11 - 12.5  | 13 - 15  | 16 - 17  | 
Mondo Pt  | 20 - 22.5  | 23 - 24  | 24.5 - 25.5  | 26 - 27  | 27.5 - 28.5  | 29 - 30  | 30.5 - 32  | 33 - 34  | 
*only available in certain models
**Some sizes are not available in all ranges. Please contact us for more information.
Youth
Y1  | Y2  | Y3  | |
|---|---|---|---|
UK  | 11 - 12  | 13 - 1  | 1.5 - 2.5  | 
Euro  | 29 - 30.5  | 31 - 32.5  | 33 - 35  | 
US  | 13 - 1.5  | 2 - 3.5  | 4 - 5  | 
Mondo  | 17 - 18.5  | 19 - 20.5  | 21 - 22.5  | 
For young active users who need reliable support as they grow.
Junior
J1  | J2  | J3  | J4  | |
|---|---|---|---|---|
UK  | 8 - 9.5  | 10 - 11.5  | 12 - 13.5  | 1 - 2  | 
Euro  | 25 - 27.5  | 28 - 29.5  | 30 - 32.5  | 33 - 34.5  | 
US  | 9 - 10.5  | 11 - 12.5  | 13 - 1.5  | 2 - 3.5  | 
Foot length (cm)  | 15 - 16.5  | 17 - 18  | 18.5 - 19.5  | 20 - 21  | 
Approx age (girls)  | 3 - 4  | 4.5 - 5.5  | 6 - 7.5  | 8 - 9  | 
Approx age (boys)  | 3 - 3.5  | 4 - 5  | 5.5 - 7  | 7.5 - 8  | 
For younger children who require comfort and stability as they start their active journey.
How to buy
Ready to purchase Formthotics products? If you are a new customer, please complete the 'Become a Provider' form. Existing customers can contact us directly to place an order.