A Complete Guide to Trimming your Insoles
Shoe sizes are not a precise science – due to differences in both measuring and manufacturing, three shoes can be of the same ‘size’ but different in length, width, and depth. Your insoles will be provided as close to your shoe size as reasonable, or possibly larger to be on the safe side, and may benefit from being trimmed to fit well into your footwear.
Insole trimming involves customizing your insoles at home to ensure that they’ve got the correct level of fit for a specific pair of shoes. It is a simple process and can be done with products found in the average home – all you need are a pen and a pair of sharp scissors.
Choose your shoes and gently lift the manufacturer’s insole.
Remove the existing insole from your shoe. Please note, whilst many insoles come out easily, some are stuck down by a thin layer of glue. This can often be gently removed, but in cases where thick and strong glues are used we would recommend not removing the insole, as this has the potential to damage your shoes.
Align your original insole to the insole you wish to modify. Always align insoles from the heel, ie line the heel up.
Carefully trace the outline of the existing insole on your new insole. Please note that while we have only altered the length of the insole in this guide, it is also possible to trim the side of the insoles to improve their fit.
Your new insole should have a clear guide for trimming. Remember, you can always trim your insoles further, but you cannot add back material that has been removed.
Using the line as a guide, carefully trim your insole. Once you’ve trimmed your insoles down to the right size, you’re ready to start wearing your insoles according to the orthotist’s advice. Remember though – just because these insoles are now perfect for these shoes, it doesn’t mean that they will be suitable for all your shoes, you may need to further trim insoles as required.
Contact numbers
We hope that you have found this information useful. If you have any questions or are worried about anything, please speak to the Orthotic Department at Dorset County Hospital on 01305 254408.
About this leaflet
Author: Nicola Green, Orthotist
Written: May 2020
Updated and approved: July 2025
Review date: July 2028
Edition: v2
If you have feedback regarding the accuracy of the information contained in this leaflet, or if you would like a list of references used to develop this leaflet, please email patientinformation.leaflets@dchft.nhs.uk
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