Finance
Amortization Calculator
Builds an amortisation schedule, which shows where the money actually goes.
Result
Extra payments are assumed to apply to principal every month from the first payment. Some lenders require you to specify this, and a few charge early-repayment penalties. Check before committing.
Get a Free Business AuditHow the calculation works
Period by period, interest is calculated on the outstanding balance and the remainder of the level payment reduces principal, with the balance carried forward. The schedule shows the interest and principal split changing over the term and the cumulative interest paid at any point.
What moves the number
- Principal, rate and term.
- Where in the term the loan currently sits.
- Extra payments and when they are made.
- Whether the rate is fixed or adjustable.
Where this one goes wrong
An extra payment early in a loan removes far more total interest than the same amount paid late, because it removes interest on that principal for every remaining period, which is why timing matters as much as amount. Pay early if paying extra. The schedule also makes the total interest visible, which is frequently a figure borrowers have never seen and which changes how they think about the term they chose.
Before you quote
- Make extra payments early rather than late if at all.
- Look at the cumulative interest figure, not just the payment.
- Rebuild the schedule after any lump sum payment.
Questions
About this calculator
Why is an early extra payment worth more?
Because it removes interest on that principal for every remaining period. The same amount paid late removes interest for only the periods left, which means timing matters as much as the amount when paying extra.
Why is the early payment almost all interest?
Because interest is charged on the outstanding balance, which is largest at the start. The split shifts gradually, and on a long term the crossover to mostly principal comes later than most borrowers expect.
Does the schedule change if rates move?
On a fixed-rate loan no; on an adjustable one the whole schedule from the adjustment onward changes. A schedule built at today's rate on an adjustable loan is a projection of one scenario rather than a plan.
Put this calculator on your site
Free to embed. Paste this where you want it to appear. It stays up to date automatically because it loads from BDEVY.
Please keep the attribution line. It is the only thing we ask in return.
How to use this calculator
- Loan amount ($). Enter your own figure; the page starts at $250,000.
- Annual interest rate (%). Enter your own figure; the page starts at 6.5%.
- Term in years. Enter your own figure; the page starts at 30.
- Extra payment per month ($). Enter your own figure; the page starts at $200.
The result updates as you type, so you can try a figure, see what it does to scheduled monthly payment, and change it back. Nothing you enter is sent anywhere or saved.
A worked example
These are the figures the calculator opens with. Every number in the results column below is produced by the same calculation the page runs, so you can follow it through before putting your own figures in.
What goes in
| Input | Value |
|---|---|
| Loan amount | $250,000 |
| Annual interest rate | 6.5% |
| Term in years | 30 |
| Extra payment per month | $200 |
What comes out
| Result | Value |
|---|---|
| Scheduled monthly payment main result | $1,580.17 |
| Interest in payment one | $1,354.17 |
| Interest saved by paying extra | $98,120 |
| Time saved | 7 yrs 11 mo |
Paying an extra 200 a month clears the loan in 22 yrs 1 mo instead of 30 years, saving $98,120 in interest.
How sensitive the answer is
Holding everything else steady and changing only loan amount, this is what happens to scheduled monthly payment. It is worth knowing which of your inputs the answer actually hinges on, and which barely move it.
| Loan amount ($) | Scheduled monthly payment |
|---|---|
| $125,000 | $790.09 |
| $187,500 | $1,185.13 |
| $250,000 example above | $1,580.17 |
| $375,000 | $2,370.26 |
| $500,000 | $3,160.34 |
Every other input is held at the example value while this one changes, which is not how a real job behaves. Treat it as a guide to which number matters most, not as five separate quotes.
What each figure means
- Loan amount ($)
- A money amount, starting at $250,000.
- Annual interest rate (%)
- A percentage, between 0 and 100, starting at 6.5%.
- Term in years
- A number, between 0 and 50, starting at 30.
- Extra payment per month ($)
- A money amount, starting at $200.
What the results tell you
| Result | What it is |
|---|---|
| Scheduled monthly payment | The headline result. A money figure. |
| Interest in payment one | A money figure. |
| Interest saved by paying extra | A money figure. |
| Time saved | A number. |
Rates and terms move
Loan and interest figures assume the rate and term you enter hold for the whole period. Variable rates, fees rolled into the balance and early-repayment terms all change the real cost.
Keep going
Related calculators
Mortgage Calculator
Works a mortgage payment, where principal and interest is only part of it.
Open calculatorLoan Calculator
Works a loan payment, where the term changes the total far more than it changes the payment.
Open calculatorDebt Payoff Calculator
Plans a debt payoff, where two orderings trade interest against momentum.
Open calculatorNumbers are only half the job
Good margins still need customers finding you and systems that hold it together. BDEVY covers the marketing, technology and automation side.