These dies are made of thin metal and cut paper beautifully. They were not meant to cut leather. We suggest trying the Sizzix or Spellbinders steel rule dies to cut any thickness of leather. They were meant to cut heavier products like chipboard, fabric, foam, leather and so much more. Sizzix calls them Bigz Dies - https://www.scrapbook.com/store/products/?w=sizzix+steel+rule+dies Here is the Spellbinders link to Steel Rule Dies... https://www.scrapbook.com/store/products/spellbinders+steel+rule+dies.html?o=9 I hope that helps.