Reference only — not financial, legal, or lending advice. Each page states the dataset and year it uses. DotGovSource is an independent private website. It is not affiliated with, endorsed by, or operated by any U.S. government agency.
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Leave blank to see the schedule by payment number instead of by date.

Monthly payment

$1,580.18

Total interest

$318,854

Total paid

$568,854

Payments

360

Add a first payment date for a payoff date

The same loan over common terms

$250,000 at 6.5% — a shorter term costs more each month and far less overall. Extra payments are excluded here so the terms compare like for like.

Monthly payment and lifetime interest by loan term
TermMonthly paymentTotal interestTotal paid
10 years$2,838.70$90,644$340,644
15 years$2,177.77$141,998$391,998
20 years$1,863.94$197,342$447,342
25 years$1,688.02$256,405$506,405
30 years$1,580.18$318,854$568,854

Amortization schedule

30 years, showing how each year splits between principal and interest. Early payments are mostly interest; the balance falls slowly at first and quickly near the end.

Amortization by year
YearPaymentsPaidPrincipalInterestBalance
112$18,962.16$2,794.43$16,167.73$247,205.57
212$18,962.16$2,981.58$15,980.58$244,223.99
312$18,962.16$3,181.25$15,780.91$241,042.74
412$18,962.16$3,394.33$15,567.83$237,648.41
512$18,962.16$3,621.65$15,340.51$234,026.76
612$18,962.16$3,864.20$15,097.96$230,162.56
712$18,962.16$4,122.99$14,839.17$226,039.57
812$18,962.16$4,399.10$14,563.06$221,640.47
912$18,962.16$4,693.72$14,268.44$216,946.75
1012$18,962.16$5,008.07$13,954.09$211,938.68
1112$18,962.16$5,343.48$13,618.68$206,595.20
1212$18,962.16$5,701.34$13,260.82$200,893.86
1312$18,962.16$6,083.16$12,879.00$194,810.70
1412$18,962.16$6,490.58$12,471.58$188,320.12
1512$18,962.16$6,925.25$12,036.91$181,394.87
1612$18,962.16$7,389.06$11,573.10$174,005.81
1712$18,962.16$7,883.92$11,078.24$166,121.89
1812$18,962.16$8,411.91$10,550.25$157,709.98
1912$18,962.16$8,975.26$9,986.90$148,734.72
2012$18,962.16$9,576.36$9,385.80$139,158.36
2112$18,962.16$10,217.71$8,744.45$128,940.65
2212$18,962.16$10,902.00$8,060.16$118,038.65
2312$18,962.16$11,632.10$7,330.06$106,406.55
2412$18,962.16$12,411.16$6,551.00$93,995.39
2512$18,962.16$13,242.35$5,719.81$80,753.04
2612$18,962.16$14,129.22$4,832.94$66,623.82
2712$18,962.16$15,075.48$3,886.68$51,548.34
2812$18,962.16$16,085.13$2,877.03$35,463.21
2912$18,962.16$17,162.38$1,799.78$18,300.83
3012$18,951.22$18,300.83$650.39$0.00

Worked example

A $300,000 loan at 6% over 30 years.

Step by step: $300,000 at 6% over 30 years
StepResultHow
Monthly rate0.5000%6% ÷ 12
Number of payments36030 years × 12
Monthly payment$1,798.66P = L × r(1 + r)^n / ((1 + r)^n − 1)
First payment splits$1,500.00 interestonly $298.66 goes to principal
Balance at the halfway point$213,144after 180 of 360 payments
Final payment splits$1,781.32 principalonly $8.91 is interest
Total interest$347,509summed across all payments
Total paid$647,509principal + total interest

Note the halfway point: after 180 of 360 payments the balance has fallen to $213,144 — well over half the original amount is still outstanding. That is the front-loading of interest, and it is why an extra payment made early removes far more interest than the same payment made late.

These figures are generated by the same engine that powers the calculator above, so they cannot drift out of step with it.

Methodology

This calculator uses the standard fixed-rate amortization formula. It works entirely from the values you enter — it does not look up rates, your credit, or any lender product.

  • Loan amount, interest rate, term, extra payment, first payment dateYour input
  • Monthly paymentCalculated on this pageP = L × r(1 + r)^n / ((1 + r)^n − 1), where r = annual rate ÷ 12 and n = number of payments
  • Per-period interest and principalCalculated on this pageinterest = remaining balance × r; principal = payment − interest
  • Total interest, total paid, payoff date, payments savedCalculated on this pageSummed across the generated schedule

How the schedule is built

Each period charges interest on the balance that is still outstanding, and whatever is left of the payment reduces the principal. Because the balance shrinks, the interest share shrinks with it — which is why early payments are mostly interest and late payments are mostly principal.

All figures are computed in whole cents rather than decimal dollars, so the schedule reconciles exactly: the principal columns sum to the loan amount, and the final balance is zero rather than a fraction of a cent. The last payment is adjusted down to settle the balance precisely instead of overshooting it.

Interest is calculated on a simple monthly basis (annual rate divided by twelve). This is the convention used for most fixed-rate mortgages, personal loans and federal student loans. It does not model daily accrual, compounding conventions used by some lenders, escrow, taxes, insurance, PMI, or fees — so a lender’s quote may differ.

A payoff date appears only if you supply a first payment date. Without one the schedule is numbered by payment instead, because assuming today’s date would produce a different answer depending on when the page happened to be built.