Debt Service Coverage Calculator Formula

Understand the math behind the debt service coverage calculator. Each variable explained with a worked example.

Formulas Used

Debt Service Coverage Ratio

dscr = annual_debt_service > 0 ? net_operating_income / annual_debt_service : 0

Annual Surplus After Debt Service

surplus = net_operating_income - annual_debt_service

Variables

VariableDescriptionDefault
net_operating_incomeNet Operating Income(USD)300000
annual_debt_serviceAnnual Debt Service (Principal + Interest)(USD)200000

How It Works

How to Calculate Debt Service Coverage Ratio

Formula

DSCR = Net Operating Income / Annual Debt Service

DSCR measures whether a business earns enough operating income to comfortably cover its debt obligations (both principal and interest). A DSCR of 1.0 means income exactly equals debt payments -- no margin for error. Lenders typically require a minimum of 1.25 to provide a safety cushion for unexpected revenue dips.

Worked Example

A company has $300,000 in net operating income and $200,000 in annual debt payments.

net_operating_income = 300000annual_debt_service = 200000
  1. 01DSCR = $300,000 / $200,000 = 1.50
  2. 02Surplus = $300,000 - $200,000 = $100,000
  3. 03The business earns $1.50 for every $1 of debt it must pay.

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