Preheat your oven to 400°F and line a rimmed baking sheet with parchment paper.
Place the bread cubes in a large bowl. Drizzle with olive oil and sprinkle garlic powder, Italian seasoning, salt, and black pepper. Toss gently until evenly coated. Spread the cubes in a single layer on the prepared baking sheet.
Bake for 15 minutes, stirring halfway through, until the croutons are golden brown and crispy. Remove from the oven and let cool completely before serving.