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How to Calculate Mortgage Payment

What is Mortgage Payment?

Mortgage payment calculation uses the standard loan amortisation formula. The monthly payment remains constant throughout the term (for fixed-rate mortgages), but the split between interest and capital changes — early payments are mostly interest.

Formula

Month 1 interest = Balance × monthly rate

Step-by-Step Guide

  1. 1Same formula as mortgage calculator: M = P × r(1+r)^n / ((1+r)^n − 1)
  2. 2Month 1 interest = Balance × monthly rate
  3. 3Month 1 capital repaid = M − interest
  4. 4Each month, interest portion decreases as balance falls

Worked Examples

Input
£200,000 at 4% over 20 years
Result
£1,212/month
Month 1: £667 interest, £545 capital

Frequently Asked Questions

What is Mortgage Payment?

Mortgage payment calculation uses the standard loan amortisation formula. The monthly payment remains constant throughout the term (for fixed-rate mortgages), but the split between interest and capital changes — early payments are mostly interest

How accurate is the Mortgage Payment calculator?

The calculator uses the standard published formula for mortgage payment. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Mortgage Payment calculator use?

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Mortgage Payment calculator use?

The core formula is: Same formula as mortgage calculator: M = P × r(1+r)^n / ((1+r)^n − 1). Each step in the calculation is shown so you can verify the result manually.

Ready to calculate? Try the free Mortgage Payment Calculator

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