Loan calculator.
Enter the terms of a private loan to see the payment, the total interest and every installment. Amortizing, interest-only and fixed-principal structures, at any payment frequency.
- Installments
- 36
- First payment
- 13 Nov 2026
- Maturity
- 13 Oct 2029
Schedule
| # | Due | Payment | Interest | Principal | Balance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 13 Nov 2026 | 760.55 | 125.00 | 635.55 | 24,364.45 | ||||||||||||
| 2 | 13 Dec 2026 | 760.55 | 121.82 | 638.73 | 23,725.72 | ||||||||||||
| 3 | 13 Jan 2027 | 760.55 | 118.63 | 641.92 | 23,083.80 | ||||||||||||
| 4 | 13 Feb 2027 | 760.55 | 115.42 | 645.13 | 22,438.67 | ||||||||||||
| 5 | 13 Mar 2027 | 760.55 | 112.19 | 648.36 | 21,790.31 | ||||||||||||
| 6 | 13 Apr 2027 | 760.55 | 108.95 | 651.60 | 21,138.71 | ||||||||||||
| 7 | 13 May 2027 | 760.55 | 105.69 | 654.86 | 20,483.85 | ||||||||||||
| 8 | 13 Jun 2027 | 760.55 | 102.42 | 658.13 | 19,825.72 | ||||||||||||
| 9 | 13 Jul 2027 | 760.55 | 99.13 | 661.42 | 19,164.30 | ||||||||||||
| 10 | 13 Aug 2027 | 760.55 | 95.82 | 664.73 | 18,499.57 | ||||||||||||
| 11 | 13 Sept 2027 | 760.55 | 92.50 | 668.05 | 17,831.52 | ||||||||||||
| 12 | 13 Oct 2027 | 760.55 | 89.16 | 671.39 | 17,160.13 | ||||||||||||
| |||||||||||||||||
| Total | 27,379.70 | 2,379.70 | 25,000.00 | ||||||||||||||
The note, the schedule above and a shared ledger, free for up to two open loans. How it works
How the figures are computed
The same arithmetic the note will use.
The rate you enter is an annual simple-interest rate. For each period, interest is the outstanding balance multiplied by the annual rate divided by the number of periods in a year, rounded to the cent. A payment covers that interest first and the rest reduces principal. The next period’s interest is computed on the reduced balance.
An amortizing loan uses a level payment found from the standard annuity formula, then trues up the final installment by the few cents that rounding leaves over. An interest-only loan pays only the period’s interest until maturity, when the principal is due in full. A fixed-principal loan divides the principal evenly across the installments and adds each period’s interest, so payments fall over the term.
A single-payment loan accrues simple interest by the day from the funding date to the maturity date, at the annual rate divided by 365. For the mechanics in detail, read how an amortization schedule works and interest-only, amortizing, or fixed principal.
Questions
- How is the monthly payment calculated?
- For an amortizing loan the payment is the level amount that, paid every period at the period rate, pays the balance to zero by the last installment. The period rate is the annual rate divided by the number of payments per year. The last payment is adjusted by a few cents so the balance ends exactly at zero.
- How is interest calculated each month?
- Interest for a period is the balance after the previous payment multiplied by the annual rate divided by the number of periods in a year, rounded to the cent. Payments apply to fees first, then interest, then principal.
- Does this calculator compound interest?
- No. Private promissory notes almost always charge simple interest on the outstanding principal, and that is what the calculator does. Interest is never charged on unpaid interest.
- What happens if I pay extra?
- An extra payment reduces principal, so every later installment carries less interest. On an amortizing loan the term shortens; on an interest-only loan the periodic interest falls. The calculator shows the scheduled case; NoteHouse recomputes a live loan after each payment.
- Is the result the same as a bank’s calculator?
- For the same inputs, yes to the cent for monthly amortizing loans, which is the standard calculation. Banks that use daily interest accrual or a 360-day year will differ by small amounts.