🏠 Mortgage Calculator
Your monthly payment is fixed, but early payments are mostly interest — the amortization schedule shows exactly how that shifts over the life of the loan. Everything runs instantly, entirely on your device.
1,798.65
monthly payment
347,515
total interest
647,515
total paid
Amortization schedule (first year + annual)
| Payment | Interest | Principal | Balance |
|---|---|---|---|
| 1 | 1,500.00 | 298.65 | 299,701.35 |
| 2 | 1,498.51 | 300.14 | 299,401.20 |
| 3 | 1,497.01 | 301.65 | 299,099.56 |
| 4 | 1,495.50 | 303.15 | 298,796.40 |
| 5 | 1,493.98 | 304.67 | 298,491.73 |
| 6 | 1,492.46 | 306.19 | 298,185.54 |
| 7 | 1,490.93 | 307.72 | 297,877.82 |
| 8 | 1,489.39 | 309.26 | 297,568.56 |
| 9 | 1,487.84 | 310.81 | 297,257.75 |
| 10 | 1,486.29 | 312.36 | 296,945.38 |
| 11 | 1,484.73 | 313.92 | 296,631.46 |
| 12 | 1,483.16 | 315.49 | 296,315.96 |
| 24 (yr 2) | 1,463.70 | 334.95 | 292,404.71 |
| 36 (yr 3) | 1,443.04 | 355.61 | 288,252.21 |
| 48 (yr 4) | 1,421.11 | 377.55 | 283,843.60 |
| 60 (yr 5) | 1,397.82 | 400.83 | 279,163.07 |
| 72 (yr 6) | 1,373.10 | 425.55 | 274,193.86 |
| 84 (yr 7) | 1,346.85 | 451.80 | 268,918.16 |
| 96 (yr 8) | 1,318.98 | 479.67 | 263,317.06 |
| 108 (yr 9) | 1,289.40 | 509.25 | 257,370.50 |
| 120 (yr 10) | 1,257.99 | 540.66 | 251,057.17 |
| 132 (yr 11) | 1,224.64 | 574.01 | 244,354.45 |
| 144 (yr 12) | 1,189.24 | 609.41 | 237,238.32 |
| 156 (yr 13) | 1,151.65 | 647.00 | 229,683.28 |
| 168 (yr 14) | 1,111.75 | 686.91 | 221,662.27 |
| 180 (yr 15) | 1,069.38 | 729.27 | 213,146.53 |
| 192 (yr 16) | 1,024.40 | 774.25 | 204,105.57 |
| 204 (yr 17) | 976.64 | 822.01 | 194,506.97 |
| 216 (yr 18) | 925.95 | 872.71 | 184,316.36 |
| 228 (yr 19) | 872.12 | 926.53 | 173,497.21 |
| 240 (yr 20) | 814.97 | 983.68 | 162,010.76 |
| 252 (yr 21) | 754.30 | 1,044.35 | 149,815.85 |
| 264 (yr 22) | 689.89 | 1,108.76 | 136,868.78 |
| 276 (yr 23) | 621.50 | 1,177.15 | 123,123.17 |
| 288 (yr 24) | 548.90 | 1,249.75 | 108,529.76 |
| 300 (yr 25) | 471.82 | 1,326.84 | 93,036.26 |
| 312 (yr 26) | 389.98 | 1,408.67 | 76,587.16 |
| 324 (yr 27) | 303.10 | 1,495.56 | 59,123.51 |
| 336 (yr 28) | 210.85 | 1,587.80 | 40,582.73 |
| 348 (yr 29) | 112.92 | 1,685.73 | 20,898.41 |
| 360 (yr 30) | 8.95 | 1,789.70 | 0.00 |
Notice payment #1 is mostly the red interest column and payment #360 is almost all green principal — that shift is the whole story of a mortgage. Principal & interest only; taxes and insurance are separate. Computed locally; your figures never leave the browser.
How the mortgage calculator works
Monthly payment M = P × r(1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is the principal, r the monthly interest rate (annual ÷ 12) and n the number of monthly payments. Each month, interest = balance × r and the rest of the payment reduces the principal.
Example: A 300,000 loan at 6% over 30 years costs about 1,799/month, with roughly 347,500 in total interest.
The eye-opening part is the amortization schedule: on a 30-year loan, the first payment can be ~75% interest and only ~25% principal, flipping over the years. That's why a single extra payment early on saves disproportionate interest, and why the "total interest" figure often rivals the loan itself. This tool covers principal and interest only — property tax, insurance and HOA fees are separate.
Frequently asked questions
How is a mortgage payment calculated?
With the standard amortizing-loan formula: the monthly payment is the principal times the monthly rate times (1+rate)^months, divided by ((1+rate)^months − 1). It's set so the loan reaches exactly zero after the final payment, keeping the payment constant throughout.
Why are early mortgage payments mostly interest?
Because interest each month is charged on the remaining balance, which is highest at the start. Early on, most of your fixed payment goes to interest and little to principal; as the balance falls, the split gradually reverses. The amortization schedule shows this month by month.
How much does an extra payment save?
A lot, especially early — because it removes principal that would otherwise accrue interest for decades. Even one extra payment in year one can shave months off the term and thousands in interest. Try it against the schedule to see the effect.
Does this include taxes and insurance?
No — it calculates principal and interest (P&I) only. Your actual monthly housing cost also includes property tax, homeowners insurance and sometimes HOA or PMI, which lenders bundle into an escrow payment.
Can I export the schedule?
Yes — download the full amortization table as a CSV to open in a spreadsheet. Everything is computed in your browser, so your loan figures never leave your device.
Is this mortgage calculator accurate and private?
Yes. It uses the standard published formula, shows its working under every result, and computes locally in your browser — your inputs are never sent to a server, and the page works offline.
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