Net worth is the single most important number in personal finance. It is calculated by subtracting everything you owe — your total liabilities — from everything you own — your total assets. If your assets exceed your liabilities, your net worth is positive. If your debts exceed your assets, it is negative. That number, whatever it is today, represents your current financial position in the most complete way possible.
Net worth is a far better measure of financial health than income. A person earning $250,000 a year who spends $260,000 a year and carries $400,000 in debt is in a worse financial position than someone earning $55,000 a year who lives below their means, owns a modest home outright, and has been investing consistently for a decade. Income tells you how much is coming in. Net worth tells you what you have actually kept and built.
This is the crucial distinction between being high-income and being wealthy. Wealth is accumulated assets minus accumulated debts. It is built slowly over years through consistent decisions: spending less than you earn, avoiding consumer debt, investing regularly, and protecting what you have built. High income accelerates the process but does not guarantee the outcome. Plenty of high earners retire with very little because they never converted their income into lasting assets.
Knowing your net worth is the starting point for every meaningful financial goal. You cannot build a retirement plan without knowing where you are starting from. You cannot decide how aggressively to pay down debt without understanding the full picture. You cannot assess whether you are on track for financial independence without benchmarking your current number. Net worth gives you the baseline that every other financial calculation requires.
Net worth changes across a lifetime in a predictable pattern for most people. It is often negative in the early twenties due to student loans and limited savings. It grows slowly through the late twenties and thirties as careers develop and debt begins to fall. It tends to accelerate sharply through the forties and fifties as mortgages are paid down, retirement accounts compound, and income peaks. Then it often plateaus or draws down in retirement as savings are spent.
Negative net worth is extremely common, especially for people under 35, and is not a permanent condition. Student loan debt, car loans, and early mortgage balances routinely push net worth into negative territory for years before savings and asset growth turn it around. What matters is the direction and trajectory of the number — are your assets growing faster than your liabilities? Every deliberate financial decision moves that number in one direction or the other.