In personal finance, a plan that assigns expected income to spending and saving categories is a budget.
A budget compares money coming in with planned uses such as housing, food, transport, debt payments, saving, and discretionary spending. It can be written on paper, managed in a spreadsheet, or tracked with an app. A budget may cover a month, a year, or another period.
The word budget comes through Old French from a term meaning a small bag or wallet. Governments, businesses, and households all use budgets, although their formats differ. A household budget is a planning tool, not a guarantee that every expense will match its estimate.
A common mix-up is treating a budget as only a list of restrictions. In practice, it can also allocate money for goals and flexible spending. A spending tracker records what happened; a budget sets expectations before or during the period.