Monthly Budget Calculator
You know money comes in every month — you just can’t say where it goes, and by day 20 the account is thinner than it should be. Enter what you earn and what you spend, and this tool shows you exactly where your money is going, whether you’re saving enough, and one specific thing to fix first.
Build your monthly budget
Use your average take-home (after-tax) monthly figures. Estimates are fine — you can refine them later.
Your budget breakdown
Here’s where every dollar of your income is going.
Fill in the calculator above to see your results.
Your personalized next step will appear here.
What a monthly budget actually tells you
A monthly budget is just a comparison: what came in, versus what went out, sorted into categories so you can see the pattern instead of just the total. Most people don’t overspend on one big thing — they leak $15 here, $40 there, across a dozen small categories, and it adds up to a number that surprises them every month. Sorting your spending into Needs, Wants, and Savings turns that fog into three numbers you can actually act on.
The formulas behind this calculator
The first formula tells you if you’re living within your means. The second tells you how fast you’re building a cushion — an emergency fund, a down payment, a retirement account — once the bills are paid.
Worked example: Sarah’s budget
Sarah is a marketing coordinator in Austin who takes home $4,500 a month after tax. Here’s how her month breaks down:
| Housing (rent) | $1,300 |
| Utilities & phone/internet | $220 |
| Groceries | $450 |
| Transportation | $300 |
| Insurance | $180 |
| Student loan minimum | $250 |
| Subscriptions & entertainment | $120 |
| Dining out & shopping | $380 |
| Savings transfer | $400 |
| Total allocated | $3,600 |
That leaves $900 unaccounted for — money that just sits in checking and quietly disappears on things Sarah can’t name in April. Once she adds that $900 to her savings transfer, her real savings rate is ($400 + $900) ÷ $4,500 = 28.9%, well past the 20% target. The lesson isn’t “spend less” — it’s that Sarah was already doing fine, she just couldn’t see it until the leftover money had a home.
Frequently asked questions
20% of take-home pay is the commonly cited target (as in the 50/30/20 rule), covering retirement, an emergency fund, and other goals combined. If you’re below that, don’t aim for 20% overnight — moving from 5% to 10% is a bigger practical win than chasing a number you’ll abandon in a month.
It’s a simple guideline for splitting after-tax income: 50% toward needs (housing, groceries, minimum debt payments), 30% toward wants (dining out, entertainment, hobbies), and 20% toward savings and extra debt payoff. It’s a starting benchmark, not a rule you need to hit exactly — the bars above show you how close you are.
Minimum payments on existing debt (student loans, car loans, credit cards) are treated as needs here, because missing them has real consequences. Anything you pay above the minimum to clear debt faster is really a form of savings — it’s building your net worth, just in reverse.
Use your average from the last 3 months for variable categories like groceries and transportation. For irregular costs (car repairs, annual insurance, holiday gifts), divide the yearly total by 12 and treat that as a monthly line item — it keeps one expensive month from wrecking your whole budget.
They’re close cousins. A cash flow statement is typically a backward-looking record of what actually happened to your money. A budget is forward-looking — a plan for where money should go before the month starts. This calculator does both: it plans the split, and once you track real spending against it, it becomes your cash flow check-in.
Keep building your financial picture