Ugg boots are designed to be worn bare-fit, providing luxurious feel of sheepskin against your skin. Because of the unique properties of wool fibres, the boots will mould to the shape of your feet, resulting in unique personal fit that can not be substituted by any other footwear.Initially, the ugg boots and other sheepskin footwear should fill snug/firm around your fit. This will allow the wool to compress and for the boot to change its shape to fit with the unique form of your foot, resulting in the perfect fit and maximum feeling of warmth and comfort, provided by the premium quality materials used in our Australian Made footwear.If you are not sure about your size, just measure your biggest foot from the back of the heel to the tip of your longest toe and use this measurement and the size chart below to workout your size. For example, if your biggest foot measures 25.1 cm (9.9") you should select AUS Men's size 7 or AUS Ladies size 8.Our ugg boots and slippers are available in full sizes only. If your feet fall between the sizes, we suggest you go up to the next size. Otherwise, choose your regular shoes size. Please do not go down in size.