In a large measuring cup or bowl, whisk together the pineapple juice, brown sugar, soy sauce, ketchup, garlic powder, and ginger until well combined.
1 ½ cups pineapple juice, ¾ cup light brown sugar, ¾ cup soy sauce, 3 tablespoons ketchup, 1 teaspoon garlic powder, ½ teaspoon ground ginger