Amortization schedule calculator
Loan Amortization Calculator A simple monthly amortization calculator when you want speed, and a full schedule builder when you need detail
See exactly where every payment goes. Get your payment, total interest and payoff date, scrub to any payment to see your remaining balance, test extra payments, biweekly, interest-only and balloon loans, then download the whole schedule for Excel or Google Sheets.
Your loan
Optional. Leave anything at 0 to ignore it.
Monthly payment
$0.00
Calculating.
Loan statement
Inspect any payment
Drag the slider to see how a single payment splits, and what you still owe afterwards.
Principal vs. interest by year
Bars show what each year of payments covers. The line is the balance still owed.
Payoff milestones
The turning points on the road to $0.
What-if lab
Each idea tested on its own against your current schedule.
Amortization schedule
Yearly view.
Same loan, different terms
Monthly payments at your amount and rate.
| Term | Payment | Total interest |
|---|
What the schedule is telling you
Plain-English notes on your numbers.
DefinitionWhat is loan amortization?
Loan amortization is paying off a loan through equal, scheduled payments that each cover that period’s interest first and put the rest toward the principal. Because interest is charged on the remaining balance, early payments are mostly interest and later payments are mostly principal, until the final payment brings the balance to exactly zero.
An amortization schedule, sometimes called an amortization table, lists every one of those payments in order: its date, how much goes to principal, how much goes to interest, and the balance left afterwards. The Consumer Financial Protection Bureau explains that lenders use a standard formula so each payment is split between principal and interest in a way that retires the loan exactly on schedule. That is the formula this calculator uses.
Most people only see one number from their lender: the monthly payment. The schedule is where the real story lives. It shows how slowly the balance falls in the early years, what you would still owe if you sold the car or refinanced the house in year five, and how much a small extra payment really saves. I built this tool so that story is visible in seconds, for any fixed-rate loan: personal loans, auto loans, mortgages, student loans, business and equipment loans.
How to use itSimple monthly mode or advanced schedule
Simple monthly is the quickest way to answer the most common question: what will my monthly payment be, and what will the loan cost in total? Enter the loan amount, interest rate and term. That is all.
Advanced schedule opens the controls that real loans need:
- Payment frequency: monthly, semi-monthly, biweekly, weekly, quarterly or annual.
- First payment date, so every row in the schedule shows a real calendar date.
- Extra principal each payment and a one-time lump sum, to see interest saved and how much sooner you are debt-free.
- Interest-only period, for loans that charge only interest for the first months or years.
- Balloon payment, for loans with payments calculated on a long term but due in full sooner.
Below the results, drag the payment inspector to any payment number to see its exact split and your remaining balance. The schedule table can show yearly totals or every single payment, and the full schedule downloads as a CSV file that opens directly in Excel, Google Sheets or Numbers.
The mathThe loan amortization formula
Payment = P × r ÷ (1 − (1 + r)−n)P = loan amount, r = annual rate ÷ payments per year, n = total number of payments
Interest this payment = balance before the payment × r
Principal this payment = payment − interest this payment
New balance = old balance − principal this payment − any extra principal
Worked example: a $25,000 personal loan
Take $25,000 at 11% for 5 years with monthly payments. The monthly rate is 0.11 ÷ 12 = 0.0091667 and n is 60. Plugging into the formula gives a payment of $543.56. The first four rows of the schedule look like this:
| Payment | Payment amount | Interest | Principal | Balance |
|---|---|---|---|---|
| 1 | $543.56 | $229.17 | $314.39 | $24,685.61 |
| 2 | $543.56 | $226.28 | $317.28 | $24,368.33 |
| 3 | $543.56 | $223.38 | $320.18 | $24,048.15 |
| 4 | $543.56 | $220.44 | $323.12 | $23,725.03 |
Payment 1’s interest is $25,000 × 0.0091667 = $229.17, leaving $314.39 for principal. Payment 2 charges interest on the new, smaller balance, so a little more goes to principal. Repeat 60 times and the balance lands on zero, with $7,613.63 paid in total interest.
Reading the tableHow to read an amortization schedule
Payment
The fixed amount due each period. With extra payments it is higher; on the final row it is usually a little lower.
Interest
The cost of borrowing for that period, charged on the balance before the payment.
Principal
The part of the payment that actually reduces what you owe. This is the column that builds equity.
Balance
What you still owe after the payment, and roughly your payoff amount on that date (lenders add interest accrued since the last payment).
Cumulative interest
Total interest paid so far. Useful at tax time if your loan interest is deductible.
Crossover point
The first payment where more goes to principal than to interest. Long loans reach it surprisingly late.
SpreadsheetsHow to make a loan amortization schedule in Excel or Google Sheets
The fastest route is to use this calculator and press Download CSV (Excel). The file opens directly in Excel, Google Sheets, LibreOffice and Numbers with dates, payment, principal, interest, extra payments, balance and cumulative interest already filled in. If you prefer to build your own, here is the exact setup I used to verify this tool. It works identically in Google Sheets.
A B 1 Loan amount 200000 2 Annual rate 6.5% 3 Years 30 4 Monthly payment =PMT(B2/12, B3*12, -B1) → 1,264.14 A (Pmt #) B (Interest) C (Principal) D (Balance) 7 1 =IPMT($B$2/12, A7, $B$3*12, -$B$1) =PPMT($B$2/12, A7, $B$3*12, -$B$1) =$B$1-C7 8 2 (fill down) (fill down) =D7-C8
Fill row 8 down to row 366 and you have all 360 payments. Two more functions answer questions people otherwise scroll for:
Interest paid in the first 5 years =CUMIPMT(B2/12, B3*12, B1, 1, 60, 0) → -63,070 (negative = money paid) Balance remaining after 60 payments =-FV(B2/12, 60, PMT(B2/12, B3*12, B1), B1) → 187,221.95
If you add extra payments, the IPMT and PPMT functions stop being accurate, because they assume the original schedule. Switch to row-by-row formulas instead: interest = previous balance × rate ÷ 12, principal = payment − interest + extra, balance = previous balance − principal. Microsoft documents each function: PMT, IPMT, PPMT and CUMIPMT.
The surpriseWhy your early payments are mostly interest
Interest is always calculated on what you still owe, and at the start you owe the most. On a $200,000, 30-year loan at 6.5%, the first year of payments totals $15,170. Only $2,235 of that reduces the balance; the other $12,934 is interest. In the final year it flips completely: $14,649 goes to principal and just $521 to interest.
This is why the crossover point matters. On that loan, principal does not overtake interest until payment 233, more than 19 years in. You do not reach half the original balance repaid until payment 257, about 21.4 years in. Understanding this helps with real decisions: refinancing or selling a few years into a long loan resets you onto the interest-heavy part of a new schedule, and extra payments made early do far more work than the same money paid late.
Auto loans and many personal loans are simple interest loans that charge interest daily on the balance. If you pay early or late within a month, your actual split will drift slightly from a standard schedule. The schedule above is still the best planning model; your lender’s statement shows the exact daily figures.
Term lengthHow the loan term changes your payment and total interest
Here is $200,000 at 6.5% across four common terms. A shorter term raises the monthly payment but cuts total interest dramatically.
| Term | Monthly payment | Total interest | Interest as % of loan |
|---|---|---|---|
| 10 years | $2,270.96 | $72,515 | 36% |
| 15 years | $1,742.21 | $113,599 | 57% |
| 20 years | $1,491.15 | $157,875 | 79% |
| 30 years | $1,264.14 | $255,089 | 128% |
On the 30-year schedule you repay the $200,000 plus another $255,089 in interest. The 15-year version costs $478 more a month but saves $141,490. For a car, the same trade-off plays out over 36 to 84 months; the Auto Loan Calculator compares those terms with trade-ins, sales tax and fees included.
Paying it off fasterAmortization schedule with extra payments
Every extra dollar of principal removes interest from every remaining payment. That is why small, regular extras are so powerful on long loans. On the same $200,000, 30-year loan at 6.5%:
| Strategy | Paid off in | Interest saved |
|---|---|---|
| $100 extra a month | 24.4 years | $55,946 |
| $250 extra a month | 19.4 years | $102,779 |
| $500 extra a month | 14.8 years | $144,148 |
| Half payment every 2 weeks | 24.2 years | $58,748 |
| $10,000 lump sum in month 12 | 26.3 years | $47,911 |
Biweekly vs. semi-monthly payments
Paying half your monthly payment every two weeks produces 26 half-payments, which equals 13 full monthly payments a year instead of 12. That extra payment is what shortens the loan. Semi-monthly payments, made twice a month, add up to exactly 12 payments a year and save almost nothing. If your lender does not offer a biweekly plan, adding one-twelfth of your payment to each monthly payment achieves nearly the same result with no fees.
Before you prepay
Check your loan agreement for a prepayment penalty, and ask your lender to apply extra money to principal rather than to next month’s payment. If you are deciding which debt to pay down first, compare interest rates: the Student Loan Repayment Calculator shows how extra payments and repayment plans change a student loan, so you can see where an extra dollar does the most good.
Recast vs. refinance
After a large lump sum, some mortgage lenders will recast the loan: keep your rate and payoff date, but recalculate a lower payment on the new balance for a small fee. Refinancing replaces the loan entirely, usually to get a lower rate, and starts a new schedule. Use this calculator twice, once with your current balance and remaining term and once with the new rate, to compare.
Special structuresInterest-only, balloon and negative amortization
Interest-only loans
During an interest-only period, payments cover interest but none of the principal, so the balance does not fall. When the period ends, the full balance must be repaid over the remaining term, and the payment jumps. On $200,000 at 6.5% with 10 interest-only years on a 30-year loan, payments start at $1,083.33 and rise to $1,491.15. Total interest climbs to $287,875, about $32,786 more than a standard schedule. Enter months in the interest-only field to model your own.
Balloon loans
A balloon loan sets payments as if the loan ran a long term, but the remaining balance falls due all at once much sooner. Payments on $200,000 at 6.5% amortized over 30 years are $1,264.14, but if a balloon is due after 7 years you would owe a single payment of $180,832.49. Most borrowers plan to refinance or sell before then, which is a risk if rates rise or values fall. Set the balloon year to see the exact amount and date.
Negative amortization
If a payment is smaller than the interest due, the unpaid interest is added to the balance, so you owe more over time instead of less. This is called negative amortization, and some payment-option loans allow it. It is why this calculator flags any setup where scheduled payments do not cover interest. Federal rules under Regulation Z restrict negative amortization in most qualified mortgages.
Fully amortizing vs. partially amortizing
A fully amortizing loan reaches zero through regular payments alone, like most car loans, personal loans and standard mortgages. A partially amortizing loan, such as a balloon loan, leaves a balance at the end that must be paid separately.
Amortization vs. depreciation
In accounting, amortization also means spreading the cost of an intangible asset, like a patent or software license, over its useful life. Depreciation does the same for physical assets such as vehicles and equipment. This calculator is about loan amortization: paying down debt.
Remaining balanceHow much will I still owe after 5 or 10 years?
This is one of the most useful and least answered questions in borrowing. Slide the payment inspector to the payment you care about and read the balance, or use the yearly schedule. On the $200,000, 6.5%, 30-year example:
- After 5 years (60 payments): you still owe $187,221.95. You have paid $75,848 in total, of which $63,070 was interest and only $12,778 reduced the balance.
- 25% repaid: payment 170, about 14.2 years in.
- 50% repaid: payment 257, about 21.4 years in.
- 75% repaid: payment 316, about 26.3 years in.
If you are planning to sell, refinance or trade in before a loan ends, the remaining balance, not the original amount, is what you need to compare against the asset’s value.
Trust and transparencyHow this calculator was built and verified
A schedule that is off by a few cents a payment compounds into a schedule that never quite reaches zero. Before publishing, I ran this calculator through four checks, and I repeat them whenever the tool changes.
1. Spreadsheet parity
Payments, interest and principal for each row match Excel’s PMT, IPMT and PPMT functions to the cent for monthly, biweekly and weekly schedules.
2. Zero-balance audit
Every schedule must end at $0.00, and total principal must equal the amount borrowed, including when extra payments, lump sums, interest-only periods and balloons are combined.
3. Hand-worked cases
The personal loan rows and the $200,000 mortgage figures in this guide were calculated by hand and cross-checked against the formula.
4. Edge cases
Zero-interest loans, one-payment loans, extras larger than the balance and balloons in the first year are all handled without errors.
What this calculator does not do: it assumes a fixed rate, payments made exactly on schedule and no fees added to the balance. Adjustable-rate loans, escrow for taxes and insurance, and daily simple-interest timing will make your lender’s figures differ. Your Truth in Lending disclosure, required under 12 CFR 1026.18, is the final word on your loan’s payment schedule.
Version history: 1.0, October 7, 2026, first published with simple and advanced modes, payment inspector, milestones and CSV export.
Keep goingRelated loan calculators
These tools from the Personal Loans and Auto collection break down monthly payments and full repayment schedules for specific kinds of borrowing. You can browse everything in the finance calculators hub.
FAQLoan amortization questions people ask
First find the payment with P × r ÷ (1 − (1 + r)^−n). Then for each payment, multiply the current balance by the periodic rate to get interest, subtract that from the payment to get principal, and subtract principal from the balance. Repeat until the balance reaches zero.
It is a calculator that needs only the loan amount, interest rate and term to return your monthly payment, total interest and a payment-by-payment schedule. Simple monthly mode on this page does exactly that.
$1,264.14 a month. Over 360 payments you pay $455,088.98 in total, of which $255,088.98 is interest.
Use =PMT(rate/12, years*12, -loan) for the payment, then =IPMT and =PPMT with the payment number for each row’s interest and principal, and subtract principal from the previous balance. Or download the CSV from this calculator, which opens directly in Excel.
Interest is charged on the balance you still owe, which is largest at the start. On a 30-year loan at 6.5%, about 86% of the first payment is interest. The share falls with every payment as the balance shrinks.
They should, but confirm with your lender. Ask for extra money to be applied to principal rather than held toward next month’s payment, and check that your loan has no prepayment penalty.
On a $200,000, 30-year loan at 6.5%, an extra $100 a month saves $55,946 in interest and pays the loan off in about 24.4 years instead of 30.
Paying half your monthly payment every two weeks makes 13 full payments a year instead of 12. On a $200,000, 30-year loan at 6.5%, that saves about $58,748 and finishes in about 24.2 years. Avoid plans that charge fees for this.
Slide the payment inspector to the payment you have just made and read the balance, or use =-FV(rate/12, payments made, PMT(rate/12, total payments, loan), loan) in Excel. Your actual payoff quote will add interest accrued since your last payment.
A large lump sum due at the end of a loan whose regular payments were not enough to pay it off. A $200,000 loan at 6.5% amortized over 30 years with a 7-year balloon leaves $180,832.49 due in year seven.
It happens when payments are smaller than the interest due, so unpaid interest is added to the balance and you owe more over time. Standard fixed-rate loans do not negatively amortize.
Yes, for any fixed-rate, fixed-payment loan. For mortgages, the payment shown is principal and interest only, without property tax, insurance or PMI. Auto and personal loans that charge daily simple interest may differ slightly if payments are early or late.
Yes. Download CSV (Excel) saves every payment with dates and cumulative interest. Copy for Sheets copies the schedule so you can paste it straight into Google Sheets or Excel, where you can format and print it.
It matches Excel’s PMT, IPMT and PPMT results to the cent and every schedule is audited to end at zero. Lender figures can differ slightly because of rounding rules, payment timing, fees or a variable rate.
Manzoor Ahmad
Founder of DexoCalc, 13+ years of web development and SEO experience
Manzoor designs, codes and tests every DexoCalc calculator himself, verifying each formula against primary sources, spreadsheet functions and hand-worked examples before it goes live. This loan amortization calculator was checked row by row against Microsoft Excel’s financial functions and the standard actuarial amortization method. Read more about Manzoor and how DexoCalc tests its tools.
Sources and references
- Consumer Financial Protection Bureau, How does paying down a mortgage work?
- Consumer Financial Protection Bureau, Regulation Z (Truth in Lending), 12 CFR Part 1026.
- Electronic Code of Federal Regulations, 12 CFR 1026.18, Content of disclosures.
- Microsoft Support, PMT, IPMT, PPMT and CUMIPMT functions.
- Board of Governors of the Federal Reserve System, G.19 Consumer Credit (current loan rates).
This loan amortization calculator provides estimates for education and planning. It assumes a fixed interest rate, payments made on schedule, interest compounded once per payment period, and no fees, taxes or insurance in the payment. Your lender’s disclosures are the final word on your loan. It is not financial, tax or legal advice.