---
title: "Mortgage Calculator: Extra Payments & Amortization"
description: "Estimate mortgage payments, taxes and insurance. Compare US, UK and Canadian conventions, extra-payment savings and a full downloadable amortization schedule."
url: "https://worldcalculators.org/calculators/mortgage/"
canonical: "https://worldcalculators.org/calculators/mortgage/"
---

# Mortgage calculator. The whole picture.

Estimate mortgage payments, taxes and insurance. Compare US, UK and Canadian conventions, extra-payment savings and a full downloadable amortization schedule.

## Quick answer

A $300,000 loan at an illustrative 6.5% annual interest for 30 years , with monthly interest and no extra payments, costs $1,896.20 per month in principal and interest. Property taxes, insurance and other costs are additional.

## Make the numbers yours

The starting values are an example, not a rate quote.
Changes labels and default interest convention; no currency conversion.

## How to calculate a monthly mortgage payment

A repayment mortgage spreads principal and interest across a set number of payments. For a fixed rate and equal monthly payments, use:
P is the amount borrowed, r is the monthly interest rate and N is the total number of payments. With a monthly convention, divide the annual percentage by 1,200 to find r. At zero interest, use P ÷ N. Canadian fixed-rate quoting commonly requires the semiannual conversion explained below.

## Principal and interest versus total housing cost

The loan payment is only part of a housing budget. Add annual property tax and home insurance, then enter any recurring mortgage insurance, HOA dues or service charges under other monthly costs. The calculator divides annual costs by 12 and adds your selected extra principal payment. Upfront purchase taxes, closing fees, repairs and utility bills are outside the estimate unless you separately include an appropriate recurring allowance.
Use the actual loan amount , not the purchase price before the down payment. If a mortgage insurance premium is financed into the loan, include it in principal. Enter the contractual interest rate rather than an APR that includes borrowing fees. The CFPB explains this distinction.

## Mortgage payment examples by convention

Illustrations only; these are not current market rates or lender offers. Each holds its rate constant and excludes extra payments and housing costs.

## What does an extra $200 a month change?

For the $300,000, 6.5%, 30-year example, adding $200 each month repays the loan in 23 years and 1 months and saves $103,448.79 in interest. This assumes all extra payments reduce principal immediately and incur no penalty. Check the prepayment privileges and charges in your own contract.

## US, UK and Canadian mortgage assumptions

Changing the market changes the display currency and default interest convention. It does not exchange currencies or apply underwriting rules. For the Canadian fixed-rate option, the monthly rate is (1 + annual rate ÷ 2)^(1 ÷ 6) − 1 , using a decimal annual rate. The FCAC sample fixed mortgage disclosure illustrates twice-yearly compounding with monthly payments.
Distinguish your mortgage term from amortization : the contract or fixed-rate deal may end years before the loan is repaid. Future renewal rates are unknown. A UK repayment mortgage or Canadian renewal therefore needs a new scenario when its rate changes. This tool does not assess affordability, qualify an application, or model interest-only and offset products.

## Sources & Methodology

Payment examples and interactive schedules use the same tested engine. Calculations keep full precision until display; assumptions and excluded costs appear alongside results.
Standards and figures reviewed 9 September 2026.

Source: https://worldcalculators.org/calculators/mortgage/
Markdown mirror of the HTML page. Prefer this URL for RAG; the interactive calculator still lives on the HTML page.