Free Budget Calculator

Your Monthly Budget

The results card updates as you type. The three boxes are targets drawn from your income and the split you chose; the figure beneath them is the part most people actually need to see.

Fill in the three optional "actually spend" fields and the headline becomes your leftover: income minus everything you assigned. A positive figure is money with no job yet. A negative figure is a shortfall, and the calculator says so in those words rather than rounding the problem away.

Open View Full Breakdown for the split applied, each target to the cent, the total you assigned and the leftover written out in full.

What Is a Budget Calculator?

A budget calculator turns one number — what you earn — into a plan for where it goes. It does not track your spending or connect to your bank. It answers a narrower and more useful question: given this income, what should each part of my spending be, and does what I actually do match?

That makes it different from an app that categorizes transactions after the fact. A monthly budget calculator is forward-looking. It is the five minutes before the month starts, not the review afterwards.

As a 50/30/20 calculator this page applies the best-known split by default, but the percentages are inputs rather than fixtures. As an expense calculator it does the second half of the job: you enter what you really spend in each category, and it reports the gap in dollars and as a share of income.

What it gives you:

• Target amounts for needs, wants and savings, from any split you choose.
• A comparison against reality, category by category, with the over or under figure.
• The leftover — including when it is negative, which is the single most actionable number here.
• A budgeting tool that stores nothing and asks for no account.

What it cannot do: tell you which costs are reasonable for your circumstances, account for irregular annual bills unless you spread them yourself, or decide where the line between a need and a want falls in your life. Those are judgments, and the page is explicit that they are yours.

For official, non-commercial budgeting material, the Consumer Financial Protection Bureau publishes free budgeting guidance and worksheets that pair well with a calculator like this one.

The 50/30/20 Rule Explained

The split is easy to state: half your take-home pay to needs, three tenths to wants, two tenths to savings and extra debt payments. Its appeal is that you can hold it in your head, which is more than can be said for most budgeting systems.

Two details are worth getting right, because they are where the split is most often misapplied:

• It runs on take-home pay, not gross salary. Tax and payroll deductions are already gone before the percentages apply.
• Minimum debt payments are a need; anything extra is savings. You cannot skip the minimum, so it belongs with the costs you must meet. Overpaying is a choice that improves your position, which is why it sits with saving.

The honest limits: the split says nothing about what you are saving for, assumes a reasonably steady income, and cannot know whether your housing market makes 50% achievable. It is a lens, not a verdict. If it does not fit, change the percentages — the calculator will not object, and neither should you.

Once you have filled in what you actually spend, this table puts the target and the reality side by side:

The last column is the one to read first. A bucket running over is not automatically a problem — if your needs exceed the target but savings still happens, the split simply does not match your circumstances and the percentages should move. It becomes a problem when the overspend lands in the leftover as a shortfall.

Needs vs Wants vs Savings: What Goes Where

Most of the difficulty in budgeting is not arithmetic. It is deciding which bucket a line item belongs in, and being honest about it.

A useful test for a need: if my income dropped sharply next month, would I still have to pay this? Rent, yes. The streaming bundle, no. Groceries, yes — but the weekly restaurant meal is a want even though both are food.

Some items sit on the line, and arguing about them wastes the time the budget was meant to save. A gym membership is a want for one person and a medical necessity for another. A car is essential in one town and optional in another. Consistency matters more than correctness here — pick a side, keep it there every month, and your month-to-month comparisons stay meaningful.

Two practical notes. Irregular bills need spreading. An annual insurance premium is a need that arrives once; divide it by twelve and treat that as a monthly cost, or it will ambush the month it lands. And be wary of reclassifying wants as needs over time — it is the most common way a working budget quietly stops working.

Budgeting When Your Income Varies

Percentage splits assume a steady paycheck. Freelancers, people on commission, hourly workers with changing shifts and anyone with seasonal work do not have one — and a budget built on a good month fails in a bad one.

The fix is to change the base, not the method:

1. Find your baseline. Look back over the last six to twelve months and identify a typical low month, or average your lowest few. That figure, not your average and certainly not your best month, is what the budget runs on.
2. Build the plan at the baseline. Enter it as your income above. If needs fit inside a low month, the budget holds all year.
3. Assign the surplus deliberately. In a better month the extra is not spending money by default. Decide in advance where it goes — topping up a buffer, savings, or debt.
4. Hold a buffer between months. With irregular income the emergency fund does double duty: it covers emergencies and it smooths the gap between a thin month and a thick one.
5. Re-check the baseline periodically. If your floor has genuinely risen, raise it — but from evidence, not optimism.

Variable income also changes the order of priorities. A larger buffer usually matters more than hitting a savings percentage, because the buffer is what stops a slow month turning into debt. Our guide on how to build an emergency fund covers how much to hold and where to keep it.

Budget Calculator vs Our Budgeting Guide

This page and our budgeting guide answer different questions, and using one when you need the other is a common source of frustration.

The honest advice is to use both, in order. Read our guide to budgeting tips that actually stick first if you have abandoned a budget before — it covers the irregular costs that wreck otherwise sensible plans, and why tracking for one month before changing anything works better than starting with rules. Then come back here and put the numbers in.

If your numbers already work and you simply want the split, the calculator alone is enough. A tool that tells you the arithmetic cannot tell you why the last three attempts collapsed in February.

How to Use This Budget Calculator

1. Enter your monthly take-home pay — what lands in your account after tax and deductions, not your gross salary.
2. Pick a split, or type your own. The presets are starting points; the three percentage fields are the real control.
3. Read the three target amounts. Before comparing anything, check whether those targets look plausible for your life.
4. Add what you actually spend in each bucket. Estimates from the last two or three months are fine — precision matters less than honesty.
5. Read the leftover. Positive means unassigned money; negative means the plan does not fit the income.
6. Adjust one thing and look again. Change the split to match reality, or change one spending figure to see what closing the gap would take.

A note on which number to act on first: if the leftover is negative, that is the only number that matters this month. Hitting a savings percentage while running a shortfall means borrowing to save, which moves you backwards.

Treat the output as a planning guideline. It assumes a monthly cycle, does not spread annual bills for you, excludes tax (your input is already after-tax), and cannot judge whether your costs are reasonable for your circumstances. Nothing you enter is stored or sent anywhere.

Our Methodology

Each target is its percentage of your take-home pay. Where the three percentages total exactly 100, the savings bucket absorbs the rounding remainder so that needs plus wants plus savings equals your income to the cent — three independently rounded percentages do not otherwise reconcile, and a split that visibly fails to add up is worse than useless.

Where the percentages do not total 100, we deliberately do not absorb the difference. Each bucket keeps the percentage you typed and the page tells you the total is not 100%. Silently rewriting your savings figure to make the arithmetic tidy would hide your typo, and we would rather show you the mistake than conceal it.

Leftover is income minus everything you assigned. When that is negative it is reported as a negative figure and labeled a shortfall. Clamping it to zero would suppress the most important thing a budget can tell anyone.

Before publication the engine was verified across 87 checks: the split proved to sum to income exactly across twelve awkward incomes including $3,333.33, $0.01 and $10,000.01; the 70/20/10 and 60/20/20 alternatives were confirmed; a non-100 split was proved to stay visibly wrong rather than being quietly corrected; overspending was confirmed to produce a negative leftover; allocations plus leftover was proved to equal income in every case; and zero-income and three-cent edge cases were each tested. All currency is rounded to cents before display.

No spending figure, income figure or "typical" household cost appears anywhere on this page. The percentages shown are the published 50/30/20 guideline and two common alternatives, presented as starting points and editable throughout.

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