Mortgage Calculator
Estimate your monthly mortgage payment, see total interest, and view a full year-by-year amortization schedule.
How it works
Three simple steps —everything happens in your browser.
Enter your loan details
Input the home price, down payment, interest rate, and loan term.
See your monthly payment
Instantly view your principal + interest, plus total cost over the life of the loan.
Compare scenarios
Adjust any parameter to see how extra payments or different rates change your total cost.
Why choose ToolKnit Mortgage Calculator?
Monthly Payment
See your estimated monthly payment update in real-time as you adjust inputs.
Amortization Schedule
Year-by-year breakdown of principal paid, interest paid, and remaining balance.
Flexible Down Payment
Toggle between percentage and dollar amount for down payment with one click.
100% Private
All calculations run in your browser. No data is sent or stored anywhere.
Pro Tips
- ● A 20% down payment eliminates PMI, saving you hundreds per month.
- ● A 15-year term means higher monthly payments but drastically less total interest.
- ● Even a 0.5% difference in interest rate can save tens of thousands over the life of a loan.
Frequently Asked Questions
How is my monthly mortgage payment calculated?+
The calculator uses the standard amortization formula, factoring in loan amount, interest rate and term in months. The result is the constant monthly principal-and-interest payment that fully repays the loan by the final month.
Does the result include taxes and insurance?+
No. The figure shows only principal and interest. Property taxes, homeowner insurance and HOA fees vary by location and lender, so they are not part of the base calculation. Expect to add ten to twenty percent for the realistic total.
Should I choose a fifteen or thirty year mortgage?+
A fifteen year loan saves a large amount of total interest but raises the monthly payment significantly. A thirty year loan is more affordable monthly but costs more over time. Toggle both and compare the numbers against your budget.
How much should I put down on a house?+
Twenty percent is the traditional benchmark because it removes private mortgage insurance. Lower down payments are possible but typically include extra fees and a higher monthly cost. The calculator lets you test different scenarios side by side.
What is an amortization schedule?+
An amortization schedule is a table showing how each monthly payment splits between interest and principal. Early payments are mostly interest, while later payments are mostly principal. The schedule helps you see when extra payments have the biggest impact.
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