Down Payment Calculator
Your down payment does two things: it sets the size of your loan, and it decides whether you pay private mortgage insurance. Conventional lenders typically require PMI when you put down less than 20%, because the loan covers more than 80% of the home's value. This down payment calculator turns a home price and a percentage into the down-payment amount and loan size, then shows the 20% figure that avoids PMI and how far a smaller down payment falls short. PMI is not permanent — it usually drops off once you build enough equity — but avoiding it from the start saves money every month.
Calculate
Default result: $40,000.00
Down Payment Calculator · Materials
calculators.dev
Down payment amount
400000 × 10
Shopping list
- Loan amount
- $360,000.00
- 20% needed to avoid PMI
- $80,000.00
- More needed to reach 20%
- $40,000.00
Est. total
$40,000.00
Estimate — confirm w/ supplier · calculators.dev
This calculator provides estimates for general informational purposes only and is not financial, investment, tax, or legal advice. Results are projections based on the figures you enter and the stated assumptions, and actual outcomes will differ. Consult a qualified financial professional before making borrowing, saving, or investment decisions.
Reviewed by the calculators.dev team · Last updated 2026-06-24
Formula reviewed against Consumer Financial Protection Bureau — private mortgage insurance and the 20% down rule
How to calculate
Enter the home price and the percentage you plan to put down. The calculator multiplies the price by the percentage for the down-payment amount, subtracts it for the loan, and computes 20% of the price as the PMI threshold. If your down payment is below 20%, the shortfall line shows how much more you would need. For a $400,000 home at 10% down, that is $40,000 down, a $360,000 loan, and $40,000 short of the $80,000 needed to skip PMI.
down payment = home price × (percent ÷ 100). loan = home price − down payment. PMI threshold = home price × 0.20 (the 20%-down / 80% loan-to-value line). shortfall = max(0, PMI threshold − down payment). Below 20% down, lenders generally add PMI until the loan-to-value ratio falls to about 80%.
Example calculation
On a $400,000 home, a 10% down payment is $40,000, leaving a $360,000 loan. Avoiding private mortgage insurance conventionally needs 20% down, which is $80,000 here — so a 10% down payment is $40,000 short of the PMI threshold. Reaching 20% would cut the loan to $320,000 and remove the monthly PMI cost.
- downPaymentAmount
- $40,000
- loanAmount
- $360,000
- pmiThreshold
- $80,000
- shortfallToAvoidPmi
- $40,000
Assumptions
- The 20% threshold reflects the common conventional-loan rule for avoiding PMI; some loan programs (FHA, VA, USDA) have different rules.
- The figures cover the down payment and loan only; closing costs, taxes, and insurance are separate.
- PMI cost itself is not estimated here — this tool shows the threshold to avoid it, not the premium.
Common mistakes
- Assuming any down payment avoids PMI — most conventional loans require 20% to skip it.
- Forgetting closing costs, which are on top of the down payment and typically 2–5% of the price.
- Draining all savings into the down payment and leaving nothing for an emergency fund or moving costs.
Frequently asked questions
How much down payment do I need to avoid PMI?
On a conventional loan, generally 20% of the home's price. On a $400,000 home that is $80,000. Putting down less usually means paying private mortgage insurance until you build about 20% equity.
Is 20% down required to buy a home?
No. Many buyers put down less, sometimes as little as 3–5%, and pay PMI. Twenty percent avoids PMI and lowers the loan, but it is not a requirement to qualify.
Does PMI ever go away?
Usually. On conventional loans, PMI typically cancels once your loan-to-value ratio reaches about 80%, either through payments or rising home value. The rules differ for some government-backed loans.
What is the difference between down payment percent and loan-to-value?
They are mirror images. A 20% down payment means an 80% loan-to-value ratio. PMI is tied to the loan-to-value ratio, so 20% down (80% LTV) is the usual line for avoiding it.