Use this calculator to determine the Home Equity Line of Credit (HELOC) amount you may qualify to receive. The line of credit is based on a percentage of the value of your home. The more your home is worth, the larger the line of credit. Of course, the final line of credit you receive will take into account any outstanding mortgages you might have. This includes first mortgages, second mortgages and any other debt you have secured by your home.