According to the shoe size chart from GrivetOutdoors.com, size 39 in the UK corresponds to a mens size 6.5 and a womens size 7.5. The shoe size conversion chart from Health and Care also confirms that UK size 39 is equivalent to a mens size 6.5 and a womens size 7.5. The international shoe size conversion chart from KiwiSizing.com also shows that a UK size 39 is equivalent to a US mens size 6, a UK womens size 6.5, and a European size 39. Therefore, size 39 in the UK can vary depending on whether it is for men or women.