Milk is an economically important agricultural commodity worldwide. Milk production is increasing, which corresponds to increasing demand and global dairy cows numbers are also increasing. Further production growth is also a prerequisite. Even in the Czech Republic, production has increased in recent years, and milk is an important agricultural commodity. A condition for maintaining current conditions, production and self-sufficiency is the long-term achievement of an adequate level of profit. Much depends on the price of milk, which fluctuates mainly depending on supply and demand on the market, and costs also significantly affect the economy. On average, for 120 dairy farms in 2021, the costs after deducting secondary outputs were 83,779 CZK per cow and year, i.e. 9.42 CZK per liter of milk sold. For farms, there was variability mainly depending on the breed and milk yield. Between 2012 and 2021, total costs increased by 17,000 CZK (26%) per cow and year and by 0.61 CZK (7%) per liter of milk sold. To evaluate economic efficiency, farms often use the income over feed cost indicator (IOFC), break-even point analysis or sensitivity analysis. The online economic tool FarmProfit, which is provided free of charge, can also be used to calculate economic indicators.