LedgerBudget apps compress complicated ideas into small labels. That is convenient until “rollover,” “available,” and “cash flow” appear to mean the same thing. They do not. Use the examples below as working definitions, and check a lender’s or app’s own terms when a contract or feature depends on exact wording.
APR (annual percentage rate)
APR expresses the yearly cost of borrowing as a percentage and may include certain fees in addition to interest. It helps compare credit offers on a common basis, though it does not tell you the exact dollar cost without a balance and repayment schedule.
Example: Carrying $1,000 for a year at a 24% credit-card APR costs roughly $240 in simple interest before compounding and changing balances. Paying the statement balance in full can prevent purchase interest, depending on the card terms.
Cash flow
Cash flow is money moving in and out over a period. Positive cash flow means inflows exceeded outflows; negative cash flow means more left than arrived. Timing matters: a profitable month on paper can still feel tight if bills arrive before income.
Example: You expect $3,000 this month and spend $2,700, a positive $300. If $2,000 of income arrives after rent and insurance are due, you can still face a short-term gap. Forecast tools are useful when they show dates, not only totals.
Emergency fund
An emergency fund is cash reserved for necessary, unpredictable costs or loss of income. It should generally be accessible and separate from money intended for routine bills. The right size depends on job stability, insurance, dependents, and how expensive your essential month is.
Example: A $900 car repair needed for commuting can be an emergency. A sale on a planned television is not. Starting with one common shock is more concrete than waiting until you can save an intimidating three or six months at once.
Fixed expense
A fixed expense is expected to stay the same for a defined period. Rent, a loan payment, or a base subscription often qualifies. “Fixed” does not mean permanent: renewal increases and contract changes still happen, so review these costs periodically.
Example: A $1,200 monthly rent is fixed during the lease. Electricity is not, even though it arrives every month. Separating fixed and variable costs helps identify what can change quickly when income falls.
Net worth
Net worth equals what you own minus what you owe. Assets can include cash, investments, and property; liabilities include loans and credit balances. It is a broad snapshot, not a measure of monthly spending room or personal worth.
Example: $8,000 in cash and investments plus a $12,000 car, minus $15,000 in debts, produces $5,000 net worth. The figure can rise while cash remains tight, so view it beside cash flow rather than as a replacement.
Reconciliation
Reconciliation means comparing an app or ledger with the source account and correcting differences until balances agree. It catches missing purchases, duplicates, mistaken opening balances, and transactions that were entered with the wrong amount.
Example: Your app says $742 but the bank says $717. A forgotten $25 cash withdrawal explains the gap. Weekly reconciliation turns an attractive dashboard into a trustworthy one. Our Spendee test includes its reconciliation results.
Rollover budget
A rollover budget carries unused or overspent category amounts into the next period. It can make irregular costs more realistic, but repeated overspending can also create a discouraging deficit if the rules are not intentional.
Example: A $60 clothing budget with $40 unspent can become $100 next month. If the app instead resets it to $60, that unused amount returns to the wider plan. Neither rule is automatically better; consistency is what makes the total meaningful.
Sinking fund
A sinking fund is money accumulated gradually for a known future expense. Unlike an emergency fund, the need is expected even if its exact price or date is uncertain. It smooths a large bill across several smaller budget periods.
Example: Saving $75 monthly creates $900 for annual insurance in twelve months. The cash may live in one savings account while the budget tracks several virtual funds, provided you do not count the same dollars twice.
Variable expense
A variable expense changes in amount or timing. Groceries, fuel, entertainment, and many utility bills fit. Variable does not mean optional: food can fluctuate and remain essential. Budgets usually control these costs with a target, range, or average.
Example: If groceries were $420, $510, and $470 over three months, a $467 average is a better starting point than the cheapest month. Add seasonality and household changes before turning that average into a hard limit.
Zero-based budget
A zero-based budget assigns every available dollar a purpose until income minus planned saving and spending equals zero. “Zero” does not mean empty accounts or spending everything. Savings, debt payments, and future expenses are valid jobs.
Example: From $3,000 available, you assign $1,900 to needs, $500 to flexible spending, $400 to savings, and $200 to debt. Nothing remains unassigned. YNAB is a well-known app built around this deliberate approach.
50/30/20 budget
The 50/30/20 framework suggests directing 50% of after-tax income to needs, 30% to wants, and 20% to saving and additional debt repayment. It is a starting proportion, not a law. High housing costs or low income can make the split unrealistic.
Example: On $3,000 take-home pay, the reference amounts are $1,500, $900, and $600. If rent alone is $1,700, calling the plan a personal failure is unhelpful. Adjust categories while preserving the core goal: essentials covered and progress funded.
Put the terms to work
Choose a method after identifying the decision you need to make. The eight-question app guide connects these definitions to real features, and our 2026 rankings show which products handle cash flow, envelopes, syncing, and shared budgets best.