Bing found the following results
UGG® Sizing Information | UGG® Official
Women's Size Guide | UGG.com
Men's Shoe Size Guide | UGG.com
Ugg size chart and fitting guide for perfect sized UGG boots
UGG Footwear Size Chart - Hibbett | City Gear
UGG® Size Chart | UGG.com
UGG Shoe Size Charts | Size Guide | Shoe & Sizing
Women's Shoes Size Chart | How to Measure | UGG® Canada
UGG Size Guide | The UGG Shop® - The Official Online Store
UGG men's and women's size chart | RunRepeat