Family Budget Calculator
A budget tells your money where to go before you spend it. One popular starting point is the 50/30/20 rule: about half of take-home income for needs, 30% for wants and 20% for saving and paying down debt. This calculator turns your income into monthly and yearly amounts for each category, and lets you change the percentages to suit your family, as long as they total 100%.
How to use the family budget calculator
- Enter your monthly income after tax.
- Keep the 50/30/20 split or change the percentages so they add up to 100%.
- Read the monthly and yearly amount for each category and compare with what you actually spend.
Formula
Each category amount = income × percentage. The split is a guideline, not a rule. Needs are things you must pay to live and work: housing, utilities, groceries, transport, insurance and minimum debt payments. Wants are things you choose. Savings include an emergency fund, retirement and extra debt repayment.
Worked examples
A $4,000 income
At 50/30/20: $2,000 for needs, $1,200 for wants and $800 for savings each month, which is $9,600 saved per year.
A tighter month
If needs take 60%, a 60/25/15 split leaves $1,000 for wants and $600 for savings out of $4,000, still a plan.
Making the budget work
What goes where
| Needs | Wants | Savings and debt |
|---|---|---|
| Rent or mortgage | Dining out | Emergency fund |
| Utilities | Streaming and subscriptions | Retirement contributions |
| Groceries | Hobbies and travel | Extra debt payments |
| Insurance and transport | Upgrades and gifts | Goals such as a home deposit |
Steps to build a budget
- Work out your take-home income.
- List fixed needs first.
- Decide your saving target and pay it first (automate if you can).
- Give the rest a purpose as wants.
- Review monthly and adjust.
An emergency fund first
Many advisers suggest building a cushion of several months of essential expenses before other goals. Start small: even a single month’s expenses helps.
When the split does not fit
Families with young children, high rents or debts may need a different split for a while. The point is to be deliberate, not to hit exactly 50/30/20.
Practice problems
Try these yourself first, then check your answer. The answers come from the calculator above.
- Split a $5,200 monthly income using 50/30/20.
Show answer
Yearly savings: $12,480.00
- Split $3,000 using 60/25/15.
Show answer
Yearly savings: $5,400.00
Common mistakes to avoid
- Basing the budget on gross pay instead of take-home pay.
- Counting a want as a need, such as an expensive car when a cheaper one would do.
- Not reviewing the budget after a change in income or expenses.
Frequently asked questions
What is the 50/30/20 rule?
A guideline that splits take-home income into 50% needs, 30% wants and 20% savings and debt repayment.
What if my needs are more than 50%?
That is common in high-cost areas. Adjust the split, look for savings in your needs and protect at least some saving.
Should debt repayment count as savings?
Extra payments beyond the minimum belong in the savings share. Minimum payments are a need.
Is this financial advice?
No. It is a planning tool; adapt it to your circumstances.
Reviewed September 26, 2026 by the SolveCalcPro editorial team. Found a mistake? Tell us; see our editorial policy.