Your IRA custodian can show you the balance. They may even offer a calculator. But when it comes to how much you're actually required to withdraw from an inherited IRA, the answer you'll usually get is: "It depends." That's not an evasion — it's the nature of inherited IRA rules. The challenge isn't the math. It's knowing which rule applies before any math begins. Here's why that distinction matters, and what beneficiaries often get wrong.