US kids to UK kids shoe size
Useful when buying from a UK store and you know your child’s US size.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter us size.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
US child size = 3 × last length (in) − 11.75; Y sizes continue the same scale after 13.5C. UK child size = 3 × last length (in) − 12; UK adult size = 3 × last − 25. So UK = US − 0.25 on the same scale.
Example
Inputs: US size = 6C. Result: UK size: 6 (child); Exact value on the UK scale: 5.75; Last length: 15.03 cm.
Limits and caveats
- The exact result always sits between two UK sizes, so the larger is shown; some store charts pick the smaller.
- Brands differ by half a size to a full size, so check the brand chart before you buy.
Questions about this tool
Why not subtract a half or a full size like some charts?
The true gap between the scales is a quarter size; charts that subtract more follow a brand’s own lasts.
What is 3Y in UK sizes?
3Y sits at 2.75 on the UK adult scale, so the tool shows size 3.
Do I need extra room on top?
The size already includes the last allowance. When your child is between sizes, the larger one lasts longer.