Decision Lab.
Work out a loan payment, see every month of the schedule, and see what extra payments would change. It explains the arithmetic; it does not tell you what to do.
This calculator is general information, not individualized tax, legal, or financial advice. It does not account for any particular situation, and it is not a substitute for advice from a professional who knows yours.
Your loan
Example figures are filled in. Change any of them.
0 is allowed. Up to four decimals.
Optional. $200.00 extra each month
Paid on top of the scheduled payment and applied only to the balance. Leave empty for none.
Paid in months 12, 24, 36 and so on.
Result
- Loan amount
- $250,000.00
- Loan term
- 30 years
- Total interest
- $318,861.58
- Total paid
- $568,861.58
- Last payment
- $1,580.55
Adjusted to clear the balance exactly, because every payment is rounded to the cent.
With your extra payments
- Lifetime interest saved
- $97,618.44
- Months eliminated
- 95
- Extra principal paid
- $52,800.00
Over the whole loan, compared with no extra payments: interest you would not owe because the balance falls sooner.
Paid off in 22 years 1 month instead of 30 years.
| Measure | Without extras | With extras |
|---|---|---|
| Time to pay off | 30 years | 22 years 1 month |
| Total interest | $318,861.58 | $221,243.14 |
| Total paid | $568,861.58 | $471,243.14 |
| Last payment | $1,580.55 | $1,278.26 |
Remaining Loan Balance
Without extra payments, the remaining balance falls from $250,000.00 to $0.00 over 360 months (30 years). Half of the loan is paid off by month 257 (21 years 5 months). With your extra payments the balance reaches $0.00 in month 265 (22 years 1 month), 95 months sooner, and half is paid off by month 177 (14 years 9 months).
| Month | Time | Balance without extras | Balance with extras |
|---|---|---|---|
| 0 | Start | $250,000.00 | $250,000.00 |
| 12 | 1 yr | $247,205.69 | $244,732.88 |
| 24 | 2 yr | $244,224.24 | $239,113.01 |
| 36 | 3 yr | $241,043.13 | $233,116.78 |
| 48 | 4 yr | $237,648.95 | $226,718.95 |
| 60 | 5 yr | $234,027.48 | $219,892.66 |
| 72 | 6 yr | $230,163.45 | $212,609.21 |
| 84 | 7 yr | $226,040.65 | $204,837.95 |
| 96 | 8 yr | $221,641.74 | $196,546.24 |
| 108 | 9 yr | $216,948.23 | $187,699.23 |
| 120 | 10 yr | $211,940.39 | $178,259.71 |
| 132 | 11 yr | $206,597.15 | $168,188.00 |
| 144 | 12 yr | $200,896.07 | $157,441.79 |
| 156 | 13 yr | $194,813.19 | $145,975.88 |
| 168 | 14 yr | $188,322.93 | $133,742.06 |
| 180 | 15 yr | $181,397.99 | $120,688.95 |
| 192 | 16 yr | $174,009.28 | $106,761.63 |
| 204 | 17 yr | $166,125.71 | $91,901.57 |
| 216 | 18 yr | $157,714.19 | $76,046.30 |
| 228 | 19 yr | $148,739.32 | $59,129.18 |
| 240 | 20 yr | $139,163.40 | $41,079.07 |
| 252 | 21 yr | $128,946.16 | $21,820.13 |
| 264 | 22 yr | $118,044.65 | $1,271.37 |
| 265 | 22 yr 1 mo | $117,103.89 | $0.00 |
| 276 | 23 yr | $106,413.04 | $0.00 |
| 288 | 24 yr | $94,002.44 | $0.00 |
| 300 | 25 yr | $80,760.69 | $0.00 |
| 312 | 26 yr | $66,632.10 | $0.00 |
| 324 | 27 yr | $51,557.30 | $0.00 |
| 336 | 28 yr | $35,472.90 | $0.00 |
| 348 | 29 yr | $18,311.31 | $0.00 |
| 360 | 30 yr | $0.00 | $0.00 |
Interest and principal, by year
Each bar splits one year of payments into interest and principal. In year 1, $16,167.73 of the payments went to interest and $2,794.31 to principal. By year 30, $651.11 of the payments went to interest and $18,311.31 to principal. Over the whole loan: $318,861.58 in interest and $250,000.00 in principal.
| Period | Interest | Principal |
|---|---|---|
| year 1, months 1–12 | $16,167.73 | $2,794.31 |
| year 2, months 13–24 | $15,980.59 | $2,981.45 |
| year 3, months 25–36 | $15,780.93 | $3,181.11 |
| year 4, months 37–48 | $15,567.86 | $3,394.18 |
| year 5, months 49–60 | $15,340.57 | $3,621.47 |
| year 6, months 61–72 | $15,098.01 | $3,864.03 |
| year 7, months 73–84 | $14,839.24 | $4,122.80 |
| year 8, months 85–96 | $14,563.13 | $4,398.91 |
| year 9, months 97–108 | $14,268.53 | $4,693.51 |
| year 10, months 109–120 | $13,954.20 | $5,007.84 |
| year 11, months 121–132 | $13,618.80 | $5,343.24 |
| year 12, months 133–144 | $13,260.96 | $5,701.08 |
| year 13, months 145–156 | $12,879.16 | $6,082.88 |
| year 14, months 157–168 | $12,471.78 | $6,490.26 |
| year 15, months 169–180 | $12,037.10 | $6,924.94 |
| year 16, months 181–192 | $11,573.33 | $7,388.71 |
| year 17, months 193–204 | $11,078.47 | $7,883.57 |
| year 18, months 205–216 | $10,550.52 | $8,411.52 |
| year 19, months 217–228 | $9,987.17 | $8,974.87 |
| year 20, months 229–240 | $9,386.12 | $9,575.92 |
| year 21, months 241–252 | $8,744.80 | $10,217.24 |
| year 22, months 253–264 | $8,060.53 | $10,901.51 |
| year 23, months 265–276 | $7,330.43 | $11,631.61 |
| year 24, months 277–288 | $6,551.44 | $12,410.60 |
| year 25, months 289–300 | $5,720.29 | $13,241.75 |
| year 26, months 301–312 | $4,833.45 | $14,128.59 |
| year 27, months 313–324 | $3,887.24 | $15,074.80 |
| year 28, months 325–336 | $2,877.64 | $16,084.40 |
| year 29, months 337–348 | $1,800.45 | $17,161.59 |
| year 30, months 349–360 | $651.11 | $18,311.31 |
| Whole loan, months 1–360 | $318,861.58 | $250,000.00 |
Schedule without extra payments
| Month | Opening balance | Payment | Interest | Principal | Closing balance |
|---|---|---|---|---|---|
| 1 | $250,000.00 | $1,580.17 | $1,354.17 | $226.00 | $249,774.00 |
| 2 | $249,774.00 | $1,580.17 | $1,352.94 | $227.23 | $249,546.77 |
| 3 | $249,546.77 | $1,580.17 | $1,351.71 | $228.46 | $249,318.31 |
| 4 | $249,318.31 | $1,580.17 | $1,350.47 | $229.70 | $249,088.61 |
| 5 | $249,088.61 | $1,580.17 | $1,349.23 | $230.94 | $248,857.67 |
| 6 | $248,857.67 | $1,580.17 | $1,347.98 | $232.19 | $248,625.48 |
| 7 | $248,625.48 | $1,580.17 | $1,346.72 | $233.45 | $248,392.03 |
| 8 | $248,392.03 | $1,580.17 | $1,345.46 | $234.71 | $248,157.32 |
| 9 | $248,157.32 | $1,580.17 | $1,344.19 | $235.98 | $247,921.34 |
| 10 | $247,921.34 | $1,580.17 | $1,342.91 | $237.26 | $247,684.08 |
| 11 | $247,684.08 | $1,580.17 | $1,341.62 | $238.55 | $247,445.53 |
| 12 | $247,445.53 | $1,580.17 | $1,340.33 | $239.84 | $247,205.69 |
Schedule with extra payments
| Month | Opening balance | Payment | Interest | Principal | Extra principal | Closing balance |
|---|---|---|---|---|---|---|
| 1 | $250,000.00 | $1,580.17 | $1,354.17 | $226.00 | $200.00 | $249,574.00 |
| 2 | $249,574.00 | $1,580.17 | $1,351.86 | $228.31 | $200.00 | $249,145.69 |
| 3 | $249,145.69 | $1,580.17 | $1,349.54 | $230.63 | $200.00 | $248,715.06 |
| 4 | $248,715.06 | $1,580.17 | $1,347.21 | $232.96 | $200.00 | $248,282.10 |
| 5 | $248,282.10 | $1,580.17 | $1,344.86 | $235.31 | $200.00 | $247,846.79 |
| 6 | $247,846.79 | $1,580.17 | $1,342.50 | $237.67 | $200.00 | $247,409.12 |
| 7 | $247,409.12 | $1,580.17 | $1,340.13 | $240.04 | $200.00 | $246,969.08 |
| 8 | $246,969.08 | $1,580.17 | $1,337.75 | $242.42 | $200.00 | $246,526.66 |
| 9 | $246,526.66 | $1,580.17 | $1,335.35 | $244.82 | $200.00 | $246,081.84 |
| 10 | $246,081.84 | $1,580.17 | $1,332.94 | $247.23 | $200.00 | $245,634.61 |
| 11 | $245,634.61 | $1,580.17 | $1,330.52 | $249.65 | $200.00 | $245,184.96 |
| 12 | $245,184.96 | $1,580.17 | $1,328.09 | $252.08 | $200.00 | $244,732.88 |
- Interest each month is the opening balance times the annual rate divided by 12, rounded to the nearest cent. This is the simplified monthly model most loan tables use. Your lender may calculate interest differently (for example daily), so its figures can differ by small amounts.
- Payments fall at the end of each month. A payment worked out from the loan amount, rate and term is rounded to the nearest cent, so the last payment is adjusted to clear the balance exactly.
- Extra principal is paid after the scheduled payment each month and never changes the scheduled payment. A yearly extra is paid in months 12, 24, 36 and so on. An extra is never larger than what is still owed, so the balance never goes below zero.
- Interest saved is the interest you would not owe because the balance falls sooner. It is not a return on the extra money, which is also paid out of your pocket. Total paid falls by exactly the interest saved.
- Everything is calculated in your browser. Nothing you enter is sent, stored or put in the address of the page.
Loans up to $1,000,000,000 and terms up to 100 years. Fees, taxes, insurance, variable rates and payment holidays are not modeled.
Your assumptions
- Loan amount
- $250,000.00
- Interest rate
- 6.5%
- Loan term
- 30 years
- Monthly payment
- $1,580.17
- Extra payments
- $200.00 extra each month
Example rate, not a forecast. Use the APY your account actually advertises.
Shown once an extra payment is entered. The savings account starts at $0.
The same extra money, two ways
Both paths have the same cash every month. One puts the extra on the loan. The other keeps paying the loan on its original schedule and saves the extra at 4% APY. They are compared on one date: the month the extra-payment loan is paid off.
That difference is the savings interest earned ($31,165.40) minus the mortgage interest avoided through month 265 ($64,605.80): -$33,440.40. Interest against interest, over the same months.
- Mortgage interest avoided
- $64,605.80
- Savings interest earned
- $31,165.40
- Months of payments eliminated
- 95
Through month 265 only. The lifetime figure on the Amortization Schedule tab reaches past this date.
The only savings figure that is earnings. The balance includes your own contributions.
After this date the savings path still pays $1,580.17 a month for 95 more months; the extra-payment path does not. Those payments, and the interest still to be charged on the balance, come after the comparison date and are not counted.
| Measure | Extra to the loan | Extra to savings |
|---|---|---|
| Savings balance | — | $84,165.40 |
| …your contributions | — | $53,000.00 |
| …interest earned | — | $31,165.40 |
| Cash held, not invested | $501.91 | — |
| Loan principal still owed | $0.00 | $117,103.89 |
| Net position (held minus owed) | $501.91 | -$32,938.49 |
Your loan’s 6.5% rate, compounded monthly, comes to about 6.697% a year, the figure to hold beside an APY. This is not your actual savings balance, and it makes no recommendation.
How this comparison works
- Both paths have the same cash every month: the scheduled payment plus the extra. Nothing is added or invented.
- The extra-payment path puts the extra on the loan. When the loan is paid off, the cash it no longer needs is held as idle cash earning nothing. It is not invested or reinvested. The only idle cash on the comparison date is what is left over in the payoff month.
- The savings path keeps paying the loan on its original schedule and puts the extra into a savings account that starts at $0. Your own savings are not assumed or used. Interest is earned each month at the rate that compounds to the APY you enter, on the opening balance, and deposits are made at the end of the month.
- The two paths are compared on one date: the month the extra-payment loan is paid off. A path’s net position is what it holds minus the loan principal it still owes. Interest not yet charged is not counted as owed.
- The difference in net position equals the savings interest earned minus the mortgage interest avoided through that date: interest against interest over the same months. A savings balance includes your own contributions, so it is never set against interest avoided.
- Not modeled: taxes on savings interest, the tax treatment of mortgage interest, fees, changing rates, and how easily you can reach the money. Money in savings stays available to you; money paid into the loan generally cannot be taken back. This comparison puts no dollar value on that.