Mortgage Calculator Calculators
Work out monthly repayments, total interest and the true cost of a mortgage.
Mortgage Calculator is a free online tool that work out monthly repayments, total interest and the true cost of a mortgage. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.
- Price
- Free: no account, no quota, no watermark
- Category
- Calculators
- Where it runs
- In your browser, on your device
- Files uploaded
- None
- Technology
- plain JavaScript
- Settings
- 5
- Works offline
- Yes, after the first visit
About Mortgage Calculator
This is a standard amortising repayment calculation: the monthly payment stays level, and the split between interest and principal shifts over the term. It covers principal and interest only. Property taxes, insurance and service charges sit on top.
How to use it
- Enter property price, deposit / down payment and interest rate.
- Adjust the remaining 2 settings if the defaults do not fit your case.
The 5 settings
| Setting | What it does | Default |
|---|---|---|
| Property price | A numeric value. | 350000 |
| Deposit / down payment | A numeric value. | 70000 |
| Interest rate | A numeric value. | 5.25% |
| Term (years) | Range 1–50. | 25 |
| Currency | Choose from 7: USD $, GBP £, EUR €, INR ₹, AUD A$, CAD C$…. | USD $ |
Under the hood
| Runs on | plain JavaScript: runs the whole thing |
| Controls | Property price, Deposit / down payment, Interest rate, Term (years), Currency |
Questions
What is not included in this payment?
Property taxes, buildings insurance, service charges, ground rent and any mortgage insurance. Depending on where you live, those can add 20–40% on top of the figure shown.
Why is total interest so much higher on a longer term?
Because you hold the debt for longer. Extending 25 years to 35 lowers the monthly payment by perhaps 15% while adding far more than that in total interest; the calculator shows both so the trade is visible.
Does this handle a fixed period followed by a variable rate?
No, it assumes one rate for the whole term. Run it twice with different rates to see the range you might be exposed to when a fixed period ends.