See exactly how every payment splits between principal and interest — with extra-payment scenarios and free CSV export.
An amortization schedule breaks a loan into its individual payments and shows, for each one, how much covers interest and how much reduces the balance. Early payments are interest-heavy because interest is charged on the full outstanding balance; as the balance falls, an ever larger share of the same payment goes to principal. That is why extra payments early in a loan save far more than the same payment near the end.
Add an amount under “Extra monthly payment” and the schedule recalculates with the extra applied straight to principal every month. Example: on a $25,000 loan at 4.35% over 5 years ($464.38/month), an extra $200 per month clears the loan in 41 months instead of 60 and cuts total interest from $2,862.29 to $1,926.93 — a saving of $935.36.
For that same $25,000 loan, the first payment of $464.38 splits into $90.63 interest ($25,000 × 4.35% ÷ 12) and $373.75 principal, leaving a balance of $24,626.25. Every following row repeats the same logic on the new, lower balance.
Interest is charged on the outstanding balance. At the start the balance is at its highest, so a large slice of each payment is interest. As the principal shrinks, the interest slice shrinks with it — the schedule makes this visible payment by payment.
Yes — the CSV export is free and contains every payment with principal, interest, balance and cumulative interest. It opens directly in Excel, Numbers or Google Sheets.
In this calculator extra payments keep the regular payment the same and shorten the loan instead (a “reduce term” strategy). That is how most private loans handle it — and it is the strategy that saves the most interest.
Yes. The math is identical for any amortized loan, bank or family. If it is a family loan, make sure the rate is at least the IRS Applicable Federal Rate — you can check that with our AFR calculator.
Family Loan Tracker turns your numbers into a live loan: payment schedule, balance tracking, automatic reminders, and a clear history both sides can see.
Monthly payment
$464.38
Total interest
$2,862
Time to payoff
5 yr
Lending this money for real?
| # | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| 1 | $464.38 | $373.75 | $90.63 | $24,626.25 |
| 2 | $464.38 | $375.11 | $89.27 | $24,251.14 |
| 3 | $464.38 | $376.47 | $87.91 | $23,874.67 |
| 4 | $464.38 | $377.83 | $86.55 | $23,496.84 |
| 5 | $464.38 | $379.20 | $85.18 | $23,117.64 |
| 6 | $464.38 | $380.58 | $83.80 | $22,737.06 |
| 7 | $464.38 | $381.96 | $82.42 | $22,355.10 |
| 8 | $464.38 | $383.34 | $81.04 | $21,971.76 |
| 9 | $464.38 | $384.73 | $79.65 | $21,587.03 |
| 10 | $464.38 | $386.13 | $78.25 | $21,200.90 |
| 11 | $464.38 | $387.53 | $76.85 | $20,813.37 |
| 12 | $464.38 | $388.93 | $75.45 | $20,424.44 |
Estimates for information only — not financial advice. Calculations run entirely in your browser; nothing you enter is stored or sent to us.