UTILITY / FIN-08
Loan & Mortgage Calculator
Find the fixed monthly payment, total interest, and total cost of a loan or mortgage, with a year-by-year amortization breakdown.
Year-by-year amortization
| Year | Interest paid | Principal paid | Balance left |
|---|---|---|---|
| 1 | $19,401.27 | $3,353.18 | $296,646.82 |
| 2 | $19,176.70 | $3,577.74 | $293,069.08 |
| 3 | $18,937.10 | $3,817.35 | $289,251.73 |
| 4 | $18,681.44 | $4,073.01 | $285,178.72 |
| 5 | $18,408.66 | $4,345.79 | $280,832.93 |
| 6 | $18,117.62 | $4,636.83 | $276,196.10 |
| 7 | $17,807.08 | $4,947.37 | $271,248.73 |
| 8 | $17,475.75 | $5,278.70 | $265,970.03 |
| 9 | $17,122.22 | $5,632.23 | $260,337.81 |
| 10 | $16,745.02 | $6,009.43 | $254,328.38 |
| 11 | $16,342.56 | $6,411.89 | $247,916.49 |
| 12 | $15,913.14 | $6,841.31 | $241,075.18 |
| 13 | $15,454.97 | $7,299.48 | $233,775.70 |
| 14 | $14,966.11 | $7,788.34 | $225,987.36 |
| 15 | $14,444.51 | $8,309.94 | $217,677.42 |
| 16 | $13,887.98 | $8,866.47 | $208,810.95 |
| 17 | $13,294.17 | $9,460.28 | $199,350.68 |
| 18 | $12,660.60 | $10,093.85 | $189,256.83 |
| 19 | $11,984.60 | $10,769.85 | $178,486.98 |
| 20 | $11,263.32 | $11,491.13 | $166,995.85 |
| 21 | $10,493.74 | $12,260.71 | $154,735.14 |
| 22 | $9,672.62 | $13,081.83 | $141,653.30 |
| 23 | $8,796.50 | $13,957.95 | $127,695.36 |
| 24 | $7,861.71 | $14,892.74 | $112,802.62 |
| 25 | $6,864.32 | $15,890.13 | $96,912.49 |
| 26 | $5,800.13 | $16,954.32 | $79,958.16 |
| 27 | $4,664.66 | $18,089.79 | $61,868.38 |
| 28 | $3,453.16 | $19,301.29 | $42,567.08 |
| 29 | $2,160.51 | $20,593.94 | $21,973.15 |
| 30 | $781.30 | $21,973.15 | $0.00 |
How a fixed monthly loan payment is calculated
Most fixed-rate personal loans, car loans, and mortgages are repaid with equal monthly payments. Early payments are mostly interest because the balance is large; later payments are mostly principal. This calculator uses the standard amortization formula for principal and interest.
Monthly payment = P × i ÷ (1 − (1 + i)−n)
i = annual rate ÷ 1,200 · n = years × 12
Total interest = monthly payment × n − P
P is the amount borrowed. When the rate is 0%, the payment is simply P ÷ n. The year-by-year table below the calculator repeats the month-by-month split and adds it up for each year.
Worked loan examples
A $300,000 mortgage at 6.5% for 30 years
The monthly rate is 6.5 ÷ 1,200 ≈ 0.5417% over 360 payments, giving a payment of $1,896.20. Across 30 years that is about $682,633 in payments, of which about $382,633 is interest. In the first year alone, about $19,401 goes to interest and only about $3,353 to principal.
A $20,000 car loan at 7% for 5 years
Over 60 payments the monthly payment is $396.02, and total interest is about $3,761.
Shorter term, higher payment, far less interest
Borrowing $250,000 at 6% costs $1,498.88 a month over 30 years (about $289,595 interest) but $2,109.64 a month over 15 years (about $129,736 interest). A longer term lowers the payment and raises the total cost.
Common loan mistakes
Comparing APR with the interest rate
A lender’s APR includes certain fees, so it is usually higher than the note rate. Enter the interest rate here to get the payment; use APR to compare the overall cost of offers.
Forgetting the rest of a housing payment
A mortgage bill often includes property tax, homeowners insurance, mortgage insurance, and sometimes HOA dues. This calculator shows principal and interest only, so your real monthly housing cost can be noticeably higher.
Limits of this estimate
It assumes a fixed rate, on-time monthly payments, no extra payments, and no fees. It does not model adjustable-rate loans, interest-only periods, balloon payments, or a lender’s exact rounding. Terms are capped at 50 years. Use your lender’s Loan Estimate for official figures.