Down Payment Calculator: method, checked example and practical limits
Calculate cash needed, resulting loan amount and progress toward a home down-payment goal. The month count is a savings plan at a constant contribution rate, rather than a forecast of future house prices.
Inputs used by this calculator
Down Payment Calculator uses the fields below. The starting values reproduce the page example; replace them with values from the same units and time period before using the result.
| Input | Starting example | Accepted value | How it is used |
|---|---|---|---|
| Target home price ($) | 400,000 | 0.01 to 1000000000000 | Supplies the target home price ($) quantity used by the published equation or result breakdown. |
| Down payment (%) | 20 | 0 to 100 | Supplies the down payment (%) quantity used by the published equation or result breakdown. |
| Closing costs (%) | 3 | 0 to 100 | Supplies the closing costs (%) quantity used by the published equation or result breakdown. |
| Cash already saved ($) | 50,000 | 0 to 1000000000000 | Supplies the cash already saved ($) quantity used by the published equation or result breakdown. |
| Monthly saving ($) | 1,500 | 0 to 1000000000 | Supplies the monthly saving ($) quantity used by the published equation or result breakdown. |
Inputs and measurement conventions
The quantities used on this page are Target home price ($), Down payment (%), Closing costs (%), Cash already saved ($), Monthly saving ($). Start with values for the same situation and read the units attached to each field. The field reference below shows supported choices and numerical limits.
A percentage closing-cost allowance may omit reserves and prepaids. Earnest money already paid should not be counted twice.
Method and equation
Multiply purchase price by the down-payment and closing-cost percentages, subtract existing savings and divide the remaining gap by monthly saving.
Down Payment Calculator uses the following stated relationship: cash needed=price×(down%+closing%); months remaining=(needed−saved)/monthly saving. Its assumptions determine which question the answer can resolve.
cash needed=price×(down%+closing%); months remaining=(needed−saved)/monthly savingWorked calculation with the starting values
Target home price ($): 400000; Down payment (%): 20; Closing costs (%): 3; Cash already saved ($): 50000; Monthly saving ($): 1500. These starting values give 42,000 remaining cash goal. The calculation breakdown is Down payment: 80,000; Closing-cost allowance: 12,000; Total cash target: 92,000; Loan before other financing: 320,000.
Twenty percent down plus 3% closing costs on $400,000 requires $92,000 before subtracting savings.
Reading the answer
The month count is a savings plan at a constant contribution rate, rather than a forecast of future house prices.
Down payment: 80,000; Closing-cost allowance: 12,000; Total cash target: 92,000; Loan before other financing: 320,000. These intermediate quantities make the stated Down Payment Calculator model inspectable; they should be read together with the main answer rather than treated as independent guarantees.
Common errors and model boundaries
A percentage closing-cost allowance may omit reserves and prepaids. Earnest money already paid should not be counted twice.
Actual cash to close includes lender credits, deposits, reserves, prepaid taxes, insurance and transaction-specific fees.
Independent verification and next decision
Closing costs and other required funds can be payable in addition to the price portion paid upfront.
For the Down Payment Calculator method, compare cash needed=price×(down%+closing%); months remaining=(needed−saved)/monthly saving with the starting inputs and the calculation table. The linked CFPB: mortgages and CFPB: Loan Estimate explainer references identify the relevant definitions, conventions or domain limitations. Retain intermediate precision when comparing a manually worked answer.
Down Payment Calculator worked-example ledger
| Quantity | Example value | Role |
|---|---|---|
| Target home price ($) | 400000 | Entered assumption |
| Down payment (%) | 20 | Entered assumption |
| Closing costs (%) | 3 | Entered assumption |
| Cash already saved ($) | 50000 | Entered assumption |
| Monthly saving ($) | 1500 | Entered assumption |
| Main answer | 42,000 remaining cash goal | Calculated from the starting inputs |
| Down payment | 80,000 | Intermediate or contextual output |
| Closing-cost allowance | 12,000 | Intermediate or contextual output |
| Total cash target | 92,000 | Intermediate or contextual output |
| Loan before other financing | 320,000 | Intermediate or contextual output |
| Saving months | 28 | Intermediate or contextual output |
Frequently asked questions
Why is the cash target above the down payment?
Closing costs and other required funds can be payable in addition to the price portion paid upfront.
Which relationship does the Down Payment Calculator use?
Multiply purchase price by the down-payment and closing-cost percentages, subtract existing savings and divide the remaining gap by monthly saving. The displayed relationship is cash needed=price×(down%+closing%); months remaining=(needed−saved)/monthly saving.
What do the starting values produce in the Down Payment Calculator?
Target home price ($): 400000; Down payment (%): 20; Closing costs (%): 3; Cash already saved ($): 50000; Monthly saving ($): 1500. These starting values give 42,000 remaining cash goal. The calculation breakdown is Down payment: 80,000; Closing-cost allowance: 12,000; Total cash target: 92,000; Loan before other financing: 320,000.
How should I interpret this Down Payment Calculator answer?
The month count is a savings plan at a constant contribution rate, rather than a forecast of future house prices.
Which input mistake most affects the Down Payment Calculator?
A percentage closing-cost allowance may omit reserves and prepaids. Earnest money already paid should not be counted twice.
What is outside this Down Payment Calculator model?
Actual cash to close includes lender credits, deposits, reserves, prepaid taxes, insurance and transaction-specific fees.
What to keep in mind
Actual cash to close includes lender credits, deposits, reserves, prepaid taxes, insurance and transaction-specific fees.
Results are rounded for display in US format, with money in dollars and cents; CSV exports keep full calculation precision. This is a calculation summary, not an official certificate.