DSCR calculator
The debt service coverage ratio (DSCR) is a rental's net operating income divided by its loan payments for a year. Lenders that offer DSCR loans use it to judge whether the rent covers the mortgage. Enter your loan and the rent, or fill them from an address.
Fill from an address (optional)
Optional: fills the price, rent estimate, taxes and HOA from the home's public Zillow page. Or just type your numbers.
Results for the worked example
- Net operating income
- $17,791
- Loan amount
- $224,000
- Monthly principal and interest
- $1,528.07
- Annual debt service
- $18,337
- Cash left after the loan (a year)
- -$546
- Cash flow is negative with these inputs: the rent doesn't cover the costs and the loan payment.
Not financial advice. These figures are estimates for illustration: plain arithmetic on the inputs shown, several of which are assumptions or estimates (see inputs). The Zestimate and rent Zestimate are Zillow's estimates, not appraisals or offers. Check every input with a lender, an insurer and a local expert before you rely on it.
Not financial advice. The results are estimates for illustration: arithmetic on the numbers shown, some of which are assumptions. The Zestimate and rent Zestimate are Zillow's estimates. Check every input before you rely on it.
Run this for any home, from your own code
The rental analysis API returns these inputs, results and the projection as JSON from a Zillow link or an address. 50 free lookups, no card.
How it's calculated
DSCR = net operating income / annual debt service
The DSCR formula
Net operating income is a year of rent, minus vacancy, minus the operating expenses (management, maintenance, capital expenditures, taxes, insurance, HOA and other costs). Annual debt service is twelve monthly principal-and-interest payments on the loan. Divide the first by the second.
A DSCR above one means the property's income covers its loan payments with some to spare; exactly one means it just covers them; below one means the owner has to pay in.
How lenders use it
Each lender sets its own minimum DSCR and its own way of working it out, so ask yours. Some divide the gross rent by the full monthly payment including taxes, insurance and HOA dues instead of using NOI. This calculator uses NOI with vacancy and operating costs counted, which usually gives a lower, more conservative ratio.
DSCR and the loan you can get
A DSCR loan is underwritten on the property's income rather than your personal income, so the ratio decides how much a lender will lend. Lenders work backwards: they take the rent, apply their own expense and vacancy rules, and size the loan so the payment fits under the income with the cushion they require.
That makes the loan term and the rate as important as the rent. A longer term lowers each payment and raises the ratio; a higher rate does the opposite. The calculator recomputes the payment from your rate and term, so you can see where the ratio crosses one.
Interest-only, adjustable and short-term rental loans
This calculator assumes a fixed-rate loan that is repaid in equal monthly instalments. An interest-only period has smaller payments, so the ratio looks higher until the principal starts; an adjustable rate can change the payment, and with it the ratio, after the fixed period ends.
Homes rented by the night are often judged on different income evidence, such as a booking history or a market study, rather than a long-term lease. Ask the lender which income figure it will accept before you rely on the result.
How to raise a low DSCR
Anything that raises the income or lowers the loan payments helps:
- A bigger down payment (a smaller loan)
- A lower interest rate or a longer loan term
- A higher rent, if the market supports it
- Lower operating costs, such as self-managing or a cheaper insurance policy
Worked example
Illustrative numbers, worked out with the same formulas as the calculator; the other inputs are the defaults below.
| Price | $280,000 |
|---|---|
| Monthly rent | $2,400 |
| Down payment | 20% |
| Interest rate (assumed) | 7.25%, 30 years |
| Vacancy, management, maintenance, capex | 5%, 8%, 5%, 5% |
| Property tax, insurance (a year) | $3,100, $1,400 |
| Step | How | Result |
|---|---|---|
| Net operating income (NOI) | effective gross income - operating expenses | $17,791 |
| Loan amount | price - down payment | $224,000 |
| Loan payments (a year) | monthly principal and interest x 12 | $18,336.90 |
| DSCR | NOI / loan payments | 0.97 |
The inputs this calculator doesn't ask for keep their defaults. Every default and estimate is listed once, with its reason, in the rental property calculator's assumptions.
DSCR calculator questions
What is a good DSCR?+
Above one, the rent covers the loan; the higher, the more cushion. Lenders set their own minimums, so check what yours requires.
Does DSCR include property taxes and insurance?+
In this calculator they are operating expenses, so they reduce the NOI. Some lenders instead add them to the loan payment; ask yours which method it uses.
Why is the DSCR not shown?+
With no loan (a full cash purchase) there is no debt service to cover, so the ratio doesn't apply.
Is the interest rate a quoted rate?+
No. The default is an assumption for illustration. Type the rate your lender quoted.
Is DSCR the same as cash flow?+
They use the same pieces. Cash flow subtracts the loan payments from NOI; DSCR divides NOI by them. A ratio above one always means positive cash flow before any other costs you add.
Will a lender accept this DSCR as calculated?+
Not necessarily. Lenders use their own rent figures, expense rules and minimums, so treat this as a preview of the conversation, not an approval. It isn't financial advice.
More free tools and the API
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- Rental analysis API referenceThe same analysis as JSON from your own code
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- Get a free API key50 free lookups, no card
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