Amortization sounds technical, but the idea is simple: each payment splits into interest (the cost of borrowing) and principal (what you still owe). At the start of a loan, interest is a big slice; near the end, principal dominates. Our calculators display a mini schedule and let you export the full table. To read it: look at payment number, interest, principal, and remaining balance. Notice the declining interest as the balance shrinks. If you add an extra $50 per month, you'll see two effects: (1) the loan ends earlier, and (2) total interest drops sharply. The schedule makes these effects concrete. Use cases: comparing a 15-year vs 30-year mortgage, seeing the benefit of refinancing at a lower rate, or planning extra payments around bonus months. The schedule isn't just a receipt—it's a roadmap for saving money.