In accounting, the break-even point formula is determined by dividing the total fixed costs associated with production by the revenue per individual unit minus the variable costs per unit. In this case, fixed costs refer to those which do not change depending upon the number of units sold. Put differently, the breakeven point is the production level at which total revenues for a product equal total expenses.
Assume an investor buys Microsoft stock at $110. That is now their breakeven point on the trade. If the price moves above $110, the investor is making money. If the stock drops below $110, they are losing money. If the price stays right at $110, they are at the BEP, because they are not making or losing anything.