How the maths works
How to use it
- Pull two or three months of actual bank statements. Do not work from memory — people underestimate variable spending by 20–30% when they guess.
- Enter every income source separately, including irregular and cash income. If income varies, use your lowest recent month, not the average. A budget that only works in a good month is not a budget.
- List expenses by category. Include the ones that do not arrive monthly — divide the annual cost by twelve and enter that (the sinking fund calculator does this for you).
- Read the Breathing Room figure. Negative is information, not a verdict.
A worked example
Take-home of $2,800 a month against $3,050 of expenses gives breathing room of −$250 and a savings rate of −8.9%. That is a $250 monthly gap, which is a specific, solvable number — very different from the vague sense that money is tight. Two levers close it and you usually need both: cut one category without misery, and raise income. Before either, call 211, which connects you to local rent, utility and food assistance most people have never heard of.
Where this sits in the Financial Literacy resource
A calculator tells you where you are. It does not tell you what to do next, and a number without a plan behind it tends to produce anxiety rather than progress. These stages are free, need no account, and cover the decision this calculator is measuring.
Common questions
What is a good savings rate?
Any positive number is a working budget when you are starting out. Around 10% is a solid early target and 20% is the common long-term guideline, but the first goal is simply getting the number above zero. A savings rate calculated on take-home pay is more useful than one calculated on gross, because take-home is the money that actually exists.
Should I budget on gross or net income?
Net — your actual take-home after tax and deductions. Budgeting on gross salary is one of the most common reasons people end up short, because it counts money that never reaches the account. If you only know your gross salary, run it through the paycheck calculator first.
What if my income is different every month?
Budget against your lowest recent month rather than the average. Treat anything above that as a surplus to assign deliberately — to the buffer, to debt, or to a tax set-aside if you are self-employed. Averaging irregular income guarantees that roughly half your months break the plan.
Is this budget calculator really free?
Yes. No account, no email, no signup. It runs entirely in your browser and nothing you type is sent to or stored on any server.
What this calculator is not
It is an educational model, not a projection and certainly not advice. It knows nothing about your income, your state, your debts or your benefits status, and it ignores taxes and fees unless the page says otherwise. If you receive SSI or SSDI some of this maths works differently and getting it wrong can cost you eligibility — start with the Disability Wealth Guide instead. Our sourcing and correction policy is on the editorial standards page.
Nothing here is stored. Every calculation runs in your browser. No numbers are transmitted, logged or saved to any server, and no account is required. Close the tab and it is gone.