Loan Calculator
Work out the monthly payment, total interest, and full amortization schedule for any fixed-rate loan. Mortgage, auto, student, personal. Runs in your browser.
Runs in your browser — nothing uploaded
Loan terms
Monthly payment
$1,580.17for 360 months
Total paid$568,861.22
Total interest$318,861.22
Principal$250,000.00
Interest share56.1%
Amortization schedule360 payments · showing first 12
| # | Payment | Interest | Principal | Balance |
|---|---|---|---|---|
| 1 | $1,580.17 | $1,354.17 | $226.00 | $249,774.00 |
| 2 | $1,580.17 | $1,352.94 | $227.23 | $249,546.77 |
| 3 | $1,580.17 | $1,351.71 | $228.46 | $249,318.31 |
| 4 | $1,580.17 | $1,350.47 | $229.70 | $249,088.61 |
| 5 | $1,580.17 | $1,349.23 | $230.94 | $248,857.67 |
| 6 | $1,580.17 | $1,347.98 | $232.19 | $248,625.48 |
| 7 | $1,580.17 | $1,346.72 | $233.45 | $248,392.04 |
| 8 | $1,580.17 | $1,345.46 | $234.71 | $248,157.32 |
| 9 | $1,580.17 | $1,344.19 | $235.98 | $247,921.34 |
| 10 | $1,580.17 | $1,342.91 | $237.26 | $247,684.07 |
| 11 | $1,580.17 | $1,341.62 | $238.55 | $247,445.53 |
| 12 | $1,580.17 | $1,340.33 | $239.84 | $247,205.69 |
A no-nonsense loan calculator for mortgages, auto loans, student loans, and personal loans on fixed-rate terms. Type the three numbers — amount, rate, term — and see your monthly payment, total interest, and the full amortization schedule. Numbers stay in your browser.
Private by design — your data never leaves your device
How to use it
No account, no upload — it all happens on your device.
1
Type the loan amount, the annual interest rate, and the term (in years or months).
2
Read the monthly payment and the totals (paid, interest, principal) instantly.
3
Scroll down to see the full amortization schedule — every payment broken into interest and principal.
4
Tap 'Show all' to expand the full schedule if your term is longer than 12 months.
What changes the monthly payment
Three numbers — small moves in each have very different effects.
| Lever | Effect on monthly | Effect on total interest |
|---|---|---|
| Loan amount | Linear — double the loan, double the payment. | Linear — double the loan, double the interest. |
| Interest rate | Smaller than you'd think — a 1% rate change moves a 30-year mortgage payment 10–15%. | Big — a 1% rate change over 30 years moves total interest by 20–25%. |
| Term length | Shorter term = bigger monthly but less total interest. Longer term = small monthly but much more interest. | Huge — a 30-year vs 15-year mortgage at the same rate can pay 2.5× the interest. |
Reading the amortization schedule
- The first payment is mostly interest. On a 30-year mortgage at 6.5%, the very first payment is about 85% interest and 15% principal. The split inverts toward the end — your last payment is almost all principal.
- Extra payments early save the most. Every extra dollar applied to principal in year 1 saves multiple dollars of interest over the life of the loan. The same dollar in year 25 saves almost nothing.
- The total interest line is the headline. A 30-year, $300,000 mortgage at 6.5% pays $382,000 in interest — more than the loan itself. Shortening the term or paying extra principal directly cuts this number.
Common pitfalls
- Comparing rates without comparing terms. A lower-rate 30-year loan often costs more in total than a higher-rate 15-year loan. Look at both monthly payment and total paid before deciding.
- Forgetting closing costs and fees. Origination fees, points, and closing costs can add 2–5% of the loan amount upfront. Roll them into your real cost of borrowing.
- Adjustable-rate loans. This calculator assumes a fixed rate. ARM (adjustable-rate mortgage) and variable-rate loans change the payment over time — use the initial rate here, then re-run with a higher rate to stress-test what happens after the adjustment period.
- Bi-weekly vs monthly schedules. Paying half the monthly amount every two weeks means 26 half payments = 13 monthly payments per year, not 12. That one extra payment a year shaves years off a 30-year mortgage. This calculator shows the standard 12-payments-per-year view.
Frequently asked
What formula does this use?
The standard fixed-rate amortization formula: M = P × r × (1+r)^n / ((1+r)^n − 1), where P is the loan amount, r is the monthly interest rate (annual ÷ 12), and n is the number of monthly payments. Each row in the schedule splits that payment into interest on the remaining balance and principal that pays the balance down.
Does this include taxes, insurance, or fees?
No. The calculator shows principal and interest only — what's commonly called "P&I" or the base loan payment. Real-world mortgage payments often add property tax, homeowner's insurance, HOA dues, and PMI on top. Auto loans may include extended warranties or documentation fees. Add those separately to know your true monthly cost.
Is my data sent anywhere?
No. Every number is plain arithmetic that runs in your browser. The loan amount, rate, and term you type are never uploaded or stored.