Preheat oven to 350°F (175°C) and line baking sheets with parchment paper or silicone mats.
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy.
Beat in the eggs one at a time, then stir in the vanilla extract.
In a separate medium bowl, whisk together the flour, cinnamon, baking soda, and salt.
Gradually incorporate the dry flour mixture into the creamed butter mixture until just combined.
Fold in the rolled oats and dried cranberries using a spatula until evenly distributed.
Drop rounded tablespoons of dough onto the prepared baking sheets, spaced approximately 2 inches apart.
Bake for 10 to 12 minutes until the edges are lightly browned but the centers remain slightly soft.
Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack for complete cooling.