Budget Calculator
Split income across needs, wants, and savings.
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Income (before taxes)
Monthly surplus
$0
Left over after expenses and savings
This splits your take-home pay across needs, wants and savings, and compares it against what you actually spend.
It uses the 50/30/20 framework by default and lets you adjust the proportions to something realistic for your situation.
How budgeting frameworks work
A budget is a plan for money you have already earned. The most widely used framework is 50/30/20: half your take-home pay to needs, 30% to wants, and 20% to savings and debt repayment.
The categories are less obvious than they sound. Needs are what you cannot avoid: housing, utilities, groceries, transport, insurance, minimum debt payments. Wants are everything discretionary. Savings covers retirement, an emergency fund, and any debt payment above the minimum.
The framework works on $5,000 of take-home: $2,500, $1,500 and $1,000. It stops working where housing is expensive. Rent of $2,200 leaves $300 for all other needs, which is not a budgeting failure so much as arithmetic.
Based on take-home pay, not gross. If your needs already exceed 50%, adjust the other two rather than abandoning the plan.
What to enter
- Monthly take-home pay
- After tax and deductions. Using gross income inflates every category by 20-30% and makes the plan unachievable.
- Fixed expenses
- Rent or mortgage, utilities, insurance, minimum debt payments. Predictable and hard to change quickly.
- Variable expenses
- Groceries, fuel, eating out, entertainment. Where a budget can realistically be adjusted.
- Savings goals
- Retirement, emergency fund and any specific target. Treating these as a fixed expense is what makes them happen.
Budgeting frameworks worth knowing
- 50/30/20
- Needs, wants, savings. Simple and flexible. Struggles where housing costs are high.
- Zero-based
- Every dollar is assigned a job until income minus assignments is zero. Precise, and takes real effort.
- Pay yourself first
- Move savings out automatically on payday and spend the rest freely. Minimal tracking, and it works.
- Envelope method
- A fixed amount per category, physical or digital, and when it is gone it is gone. Strong for controlling variable spending.
What this assumes
Percentages are guidance, not rules. The right split depends on your housing cost, income and stage of life.
Irregular costs matter. Car registration, annual insurance and holidays need a monthly set-aside or they arrive as a shock.
How to calculate your monthly budget
Start from take-home pay, sort actual spending into the three categories, and compare against the targets.
- take-home
- After tax and deductions, not gross
- savings
- Includes debt payments above the minimum, which is genuinely building net worth
Work out real take-home pay. Use your actual deposit. If you are paid biweekly, multiply by 26 and divide by 12 rather than doubling a cheque.
Sort three months of actual spending. Go through statements rather than estimating. Nearly everyone finds a category that is much larger than they thought.
Compare against the targets. The gap tells you where to look. If needs are above 50%, that is the structural problem and the others cannot fix it.
Adjust the split to something you will follow. 60/20/20 in a high-cost city is a real budget. 50/30/20 that you abandon in six weeks is not.
See a worked example: where the rule stops working
- Take-home
- $5,000 a month
- Rent
- $2,200
50/30/20 targets: $2,500 needs, $1,500 wants, $1,000 savings.
Rent alone is $2,200 of the $2,500 needs budget, leaving $300 for utilities, groceries, transport and insurance.
That is not achievable, so something has to give. Cutting wants to 20% frees $500 and gives a 60/20/20 split.
The alternative levers are the structural ones: a cheaper home, a housemate, or more income. Worth naming, because no amount of category discipline solves a housing cost that high.
60/20/20 is the honest split here
Frequently asked questions
Fifty per cent of take-home pay to needs, 30% to wants, 20% to savings and debt repayment beyond the minimums.
It is popular because it is easy to remember and does not require detailed tracking. It is guidance rather than a rule, and adjusting the proportions is normal.
Take-home, after tax and deductions. Using gross overstates every category by roughly 20-30% and produces a budget you cannot actually follow.
If you contribute to a 401(k) through payroll, that already counts towards the savings 20% even though it never reaches your account.
Then 50/30/20 does not apply and forcing it will not help. Move to something like 60/20/20 and be deliberate about what you are trading away.
It is worth naming the real levers: reducing housing cost, adding a housemate, or increasing income. Trimming small discretionary spending cannot close a gap of that size.
Minimum payments are needs, because missing them has consequences. Anything above the minimum counts as savings, since it is building net worth.
That split is useful in practice: it means an aggressive payoff plan counts towards your 20% rather than competing with it.
Budget on your lowest typical month, not your average. Anything above that goes to a buffer account first, then to savings.
The buffer is what turns a variable income into a stable one. Once it holds two or three months of expenses, you can pay yourself a consistent amount from it.
Sinking funds. Add up the annual cost of car registration, insurance premiums, holidays and gifts, divide by twelve, and set that aside monthly.
These are the costs that break budgets, because they are entirely predictable and still arrive as a surprise. They belong in the needs category, spread across the year.
Problems people actually run into
Budgeting on gross income
A $6,000 gross salary is not $6,000 to allocate. After tax, payroll tax, insurance and retirement contributions, it may be $4,300.
Building a budget on the larger figure means overspending every single month by the difference, and concluding that budgeting does not work.
Estimating spending instead of checking it
People consistently underestimate variable spending, particularly food, subscriptions and small frequent purchases.
Go through three months of actual statements before setting any targets. The point of the exercise is usually what you find, not the percentages you land on.
Results are estimates for general information only and are not professional financial, medical, or legal advice. Read our full disclaimer.
Last updated: September 4, 2026