As all our garments are sourced from various different indie labels you'll find a size chart included as an image on every product page. This size chart will match the garment you are looking at. Any details (i.e. if it's a small or larger fit) will be included in the text of that page.
For a rough conversion...
XS = size 6
S = size 8
M = size 10
L = size 12
XL = size 14
I would recommend following the size guide attached to each product for correct fit and to avoid unnecessary returns.
If you have any questions regarding the products or fit, please contact me, Sarah, via firstname.lastname@example.org
Below is a rough international conversion scale...