Zero-Based Budget Calculator

How it is calculated

The tool does one subtraction: remaining = monthly income − total allocated. Monthly income is the money you expect this month, in dollars, after tax; total allocated is the sum of every amount you have already given a job, including bills, groceries, savings transfers, debt payments and any investing. You add up the categories yourself and enter a single total, since the tool has no separate rows. A result of exactly zero means the budget is balanced in the zero-based sense. A positive remainder is money still without a job, and a negative remainder, shown with a minus sign, means you have planned more spending than income. Zero is accepted for either field; negative or empty values return no result. The tool does not check whether the allocations are realistic.

Common mistakes

• Entering gross pay instead of take-home pay. A budget has to be built on the money that actually arrives in your account.
• Leaving out irregular costs such as annual insurance, gifts or car repairs. If they are not in the allocated total, the remainder looks larger than it is.
• Treating the remainder as free money to spend. In a zero-based budget the leftover should be assigned to something, such as savings or debt, until it reaches zero.
• Counting a savings transfer as not allocated. Money moved to savings or debt payoff is allocated, and it belongs in the total.
• Budgeting with a variable income by using an optimistic month. Use a conservative figure, and assign any extra when it arrives.