Work out your home down payment, the loan amount left to finance and the estimated monthly mortgage payment, and check whether you reach the 20% threshold.
Advanced: currency symbol
The full bar is the home price. The green part is the cash you bring; the blue part is the mortgage you take out and repay over the loan term.
| Down payment | Cash down | Loan amount | Monthly payment |
|---|
Each row keeps your home price, rate and term fixed and changes only the down payment percent. A larger down payment means a smaller loan and a lower monthly payment.
For beginners: how to read this result
Describe the task to the AI assistant and continue from the result.
Open AI assistant →To get a result, pick one of the preset scenarios or enter your own figures: the home price, the mortgage interest rate and the loan term in years. Then choose how you want to set the down payment and the calculator returns the cash you put down, the loan you finance and the estimated monthly payment.
The two down payment modes
The mode toggle changes which input is shown so you only fill in the one you actually have.
- By percentage — you enter a down payment percent, with quick 5%, 10% and 20% buttons. The down payment amount is calculated as that percent of the home price. The fixed-amount field is hidden in this mode.
- By amount — you enter a fixed cash amount you plan to put down. The percent is then calculated from the home price. The percent field and its preset buttons are hidden in this mode.
How the math works
The down payment is the cash you pay up front. The loan amount equals the home price minus the down payment. The estimated monthly payment uses the standard amortization formula: the monthly payment equals the loan amount times the monthly interest rate, divided by one minus one plus the monthly rate raised to the power of minus the number of monthly payments. The monthly rate is the yearly rate divided by twelve, and the number of payments is the loan term in years times twelve.
The 20% threshold
Putting down at least 20% of the home price is the common point at which lenders stop charging extra mortgage insurance. The calculator states clearly whether your down payment meets that mark, and if it does not, how much more cash would be needed to reach it. The comparison table lists down payments of 5%, 10%, 15%, 20% and 25% with their loan amount and monthly payment, and highlights the rows that clear the threshold.
What is not included
The monthly payment shown covers loan principal and interest only. It does not include mortgage insurance, property tax, homeowner’s insurance, closing costs, legal or appraisal fees, or moving costs. The 20% figure is a widely used guideline rather than a fixed rule for every lender. Treat the result as a planning estimate and confirm the exact terms and minimum down payment with your own lender before deciding.