Amortization Calculator
Generate a full loan payment schedule showing principal, interest and balance every month
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Full Amortization Schedule
| Period | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| 📊 Calculate above to generate your schedule | ||||
What Is an Amortization Schedule?
An amortization schedule is a complete table of periodic loan payments showing the amount of each payment that goes toward principal and interest, along with the remaining balance after each payment. It shows you exactly how your loan is paid off over time.
How Amortization Works
In the early months of a loan, most of your payment goes toward interest because the outstanding balance is high. As you pay down the principal, the interest portion shrinks and more of each payment goes toward reducing what you owe. This is why the total interest on a 30-year mortgage can exceed the original loan amount.
The Power of Extra Payments
Making even small extra payments each month can dramatically reduce the total interest paid and shorten your loan term. On a £200,000 mortgage at 6.5% over 30 years, paying an extra £200 per month saves over £60,000 in interest and pays the loan off 7 years early. Use the Extra Payment field above to see the impact for your loan.
Why Does Interest Front-Load?
Interest is charged on the outstanding balance each period. Since the balance is highest at the start of the loan, so is the interest. As principal is paid down, the balance falls and interest charges decrease — this is why early payments feel like they make little dent in the balance.
Reading an Amortization Schedule Like a Pro
Built and verified by Andrius R. · Updated June 2026
An amortization schedule is the full X-ray of a loan: every payment split into its interest and principal parts, month by month, until zero. Once you can read one, several "mysteries" of borrowing — why early payoff saves so much, why refinancing resets your progress — become obvious.
Why the split changes every single month
The payment stays constant; the recipe inside it doesn't. Each month, interest is charged on whatever balance remains — so as the balance falls, the interest portion shrinks and the principal portion grows by exactly the same amount. It's a seesaw inside a fixed payment.
Monthly payment: $1,580.17. In month one, interest is 250,000 × (0.065 ÷ 12) ≈ $1,354 — so only ~$226 reduces the debt. Across the whole first year you pay about $18,962, of which roughly $16,168 is interest and just $2,794 is principal: after twelve payments you still owe ~$247,206.
The crossover point — the first month where more of your payment goes to principal than interest — doesn't arrive until month 233, about 19 years 5 months in. More than half this loan's life passes before you're mostly paying yourself.
The practical consequences of that lopsided start
- Early extra payments punch far above their weight. Every extra dollar in year one kills a dollar of balance that would otherwise be charged interest for decades. The same dollar in year 25 saves only a few years of interest.
- Selling or refinancing early means you've built little equity from payments. After 5 years on the example loan you've paid ~$94,800 but reduced the debt by only ~$16,000 — the rest was interest. (Market appreciation and your down payment, not the payment schedule, are what build early equity.)
- Refinancing restarts the clock. A new 30-year loan begins back at the interest-heavy end of the seesaw. Refinancing 8 years into a mortgage at a lower rate can still cost more in lifetime interest if you stretch back out to 30 years — compare against refinancing into a shorter term.
Loans that don't amortize like this
Knowing the standard pattern helps you spot the exceptions: interest-only loans (no principal reduction at all during the IO period), balloon loans (small payments, then one large final lump), negative amortization (payments below the interest charge, so the balance grows — historically a feature of the riskiest mortgages), and revolving credit like credit cards, which have no fixed schedule at all. If a loan offer's schedule doesn't show the balance falling every month, that's the part to question.
Using the schedule to make decisions
Generate the table above for your real loan, then try scenarios: add a fixed extra monthly amount and watch the payoff date and total interest move; check the balance at the year you might sell; compare the crossover point across different terms. The schedule turns "should I pay extra?" from a feeling into a number — and for the strategy side of that question, see our guide links and the mortgage calculator's worked examples.
// Pay Extra Early
Extra payments made early in the loan term save the most interest — the earlier, the higher the remaining balance they reduce.
// Bi-Weekly Trick
Paying half your monthly payment every two weeks results in one extra full payment per year, shaving years off a mortgage.
// Refinancing
If rates drop significantly, refinancing resets your amortization. Run both scenarios to see if the savings outweigh closing costs.
// Lump Sums
Tax refunds, bonuses, or windfalls applied directly to principal can save substantial interest over the life of a loan.