What are the principles of break even analysis?

To calculate your break even point you need to total your fixed costs and your variable costs (separately) . The equation is fixed costs ÷ (price - variable costs). Variable costs are your costs associated with production. If u produce one additional unit variable cost will increase and fixed costs will not. When you reach your break even point you have covered all if your fixed costs (for the month, for example). All units sold after break even will bring net income for the period since your fixed costs are covered.