Sizes in EU, UK and US on underwear
Short answer: Conversion charts are only a rough guide, not exact. Always use the centimeter measurements, especially for bras and underwear where the systems differ the most.
Why conversion is tricky
EU, UK and US use different starting points for their sizing systems, and there is no fixed formula between them. An EU size thirty eight roughly matches UK ten and US six, but only roughly. For underwear the gap grows wider, since there is no extra fabric to absorb the difference.
Bras are the hardest
Band and cup are calculated differently across the three systems, and cup letters do not follow a straight line across countries. Measure under the bust and across the fullest point in centimeters, and use the maker's own chart rather than a general conversion table. See bamboo bra without underwire.
Panties and underpants
Here hip measurement in centimeters is the only thing that really counts, regardless of which country the brand comes from. Letter sizes cover a wide range, and two brands can use the same letter for very different measurements. See bamboo panties and bamboo underpants for men.
How to handle it in practice
Write your measurements down in centimeters and keep them ready whenever you order from a new place, whichever country it ships from. That way the system stops mattering, and you avoid converting back and forth between letters and numbers every time. See bamboo underwear for women.
Socks have their own system too
Sock sizes usually follow shoe size in that country, but the scale is not always identical from brand to brand. Check whether a foot length in centimeters is printed on the packet, since that is far more reliable than the number or letter size itself.
Some brands use several systems at once
A handful of international brands list EU, UK and US together on the same label to make things easier for customers in different countries. This is convenient, but still double check the centimeter figure, since even these listings can be approximate and vary slightly between collections.
Historical background behind the differences
The systems developed independently in each country, often based on local body measurements and industry standards from the twentieth century. That is why they were never brought into line globally, even though trade today happens across borders around the clock.
When unsure, choose by the centimeter figure
If the choice is between a letter size and a centimeter measurement, always pick the centimeter figure when both are available on the page. That is the number that actually describes the body, while letters are just a translation that can go wrong between countries.
Frequently asked questions
Is there a reliable conversion chart
No, only approximate ones exist. A maker's own size chart is always more accurate than a general chart, because it matches that specific brand's own cut.
Is clothing from the UK smaller than the EU
Often slightly smaller, but it varies more between brands than between countries generally. Trust each brand's own chart rather than the country it ships from.
What about sock sizes
They usually follow shoe size within that system and therefore also need converting whenever you order from a country other than the one you are used to.
See our range of Boody underwear.
