A measure of a company's financial leverage calculated by dividing its total liabilities by owners equity. It indicates what proportion of equity and debt the company is using to finance its assets.
Debt to equity Ratio= Total liabilities/Owners equity
Note: Sometimes only interest-bearing, long-term debt is used instead of total liabilities in the calculation.
To clarify, only use non-current (interest bearing) liabilities if the question specifically requires it but if in doubt just use total liabilities.
hope that helps