# Amortization Calculator

URL: https://speedycalculator.com/calculators/finance/amortization/
Last updated: 2026-10-25

> The amortization calculator works out the periodic payment for any loan, with any compounding (including continuous) and payment frequency, plus an optional extra payment – showing the number of payments, total interest, and the interest and principal of the first payment.

## Inputs

- Loan amount
- Loan term (years, months)
- Interest rate (%)
- Compounding frequency
- Payment frequency
- Extra payment per period

## Results

- Number of payments
- Payment per period
- Payments needed (with extra payment)
- Total interest
- Total of payments
- Interest in the first payment
- Principal in the first payment
- Interest saved by the extra payment

## Formula

```
Rate per payment i = (1 + r ÷ m)^(m ÷ p) − 1 (continuous: e^(r/p) − 1)
Payment = L × i ÷ (1 − (1 + i)^−n)
With extra payment E: number of payments = nper(i, payment + E, L)
```

## Explanation

An amortizing loan is repaid with equal payments that cover the interest due and part of the principal. Early payments are mostly interest; the principal share grows each period.

### How to use the Amortization Calculator

- **Loan amount**
- **Loan term**
- **Interest rate**
- **Compounding frequency**
- **Payment frequency**
- **Extra payment per period**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter the loan amount, term, interest rate, compounding, payment frequency and any extra payment per period.

### Tips

- Compare loans by APR and total cost, not just the monthly payment.
- Extra payments go straight to principal and can save a lot of interest.
- Pay off the highest-rate debt first if you want to save the most money.
- Check for prepayment penalties before paying a loan off early.

### Common mistakes to avoid

- Stretching a loan term to lower the payment without seeing the extra interest.
- Paying only the minimum on credit cards.
- Forgetting fees that are rolled into the loan.

### Inputs explained

FieldWhat to enterLoan amountAmount in your currencyLoan termUnits: years, monthsInterest rateIn %Compounding frequencyChoose one: Yearly, Semi-annually, Quarterly, Monthly …Payment frequencyChoose one: Monthly, Semi-monthly, Bi-weekly, Weekly …Extra payment per periodAmount in your currency

### What each result means

- **Number of payments** = round([Loan term]×[Payment frequency])
- **Payment per period** = pmt([Rate per payment], [Number of payments], [Loan amount])
- **Total interest** = ([Payment per period] + [Extra payment per period])×[Payments needed (with extra payment)] - [Loan amount]
- **Total of payments** = ([Payment per period] + [Extra payment per period])×[Payments needed (with extra payment)]
- **Interest in the first payment** = [Loan amount]×[Rate per payment]
- **Principal in the first payment** = [Payment per period] + [Extra payment per period] - [Loan amount]×[Rate per payment]
- **Interest saved by the extra payment** = ([Payment per period]×[Number of payments] - [Loan amount]) - [Total interest]

### Example values

How the main result changes when **Loan amount** changes and everything else stays at the example values above:

Loan amountPayment per period125,000790.09187,5001,185.13250,0001,580.17312,5001,975.21375,0002,370.26500,0003,160.34

## Worked example

Inputs — Loan amount: $250,000; Loan term: 30 years; Interest rate: 6.5 %; Compounding frequency: Monthly; Payment frequency: Monthly; Extra payment per period: $0.

Results — Number of payments = 360; **Payment per period = $1,580.17**; Payments needed (with extra payment) = 360; Total interest = $318,861.22; Total of payments = $568,861.22; Interest in the first payment = $1,354.17; Principal in the first payment = $226.00; Interest saved by the extra payment = $0.00.

## FAQ

**What is loan amortization?**
Repaying a loan in equal instalments that cover interest and principal.

**How does compounding affect the payment?**
More frequent compounding slightly raises the effective rate.

**Do extra payments reduce interest?**
Yes – they go straight to principal, so less interest accrues.

**What formula does the Amortization Calculator use?**
Rate per payment i = (1 + r ÷ m)^(m ÷ p) − 1 (continuous: e^(r/p) − 1).


## Sources

- [Consumer Financial Protection Bureau](https://www.consumerfinance.gov/)