A free monthly budget calculator — built around the calendar month your bills actually follow
Monthly Budget Calculator
Most of your largest costs — rent or mortgage, the electric bill, the phone plan, the streaming subscriptions — arrive on a calendar-month schedule. A monthly budget lines your income up against those month-shaped obligations and shows what is genuinely left over when the month closes. Clear Budget describes and calculates; it does not recommend financial decisions.
- 100% free
- Private by design
- Calendar-month totals
- Multi-currency budgeting
01— The basics
What makes a monthly budget different
A monthly budget is a plan for one calendar month — January, February, March and so on. That sounds obvious, but the calendar month is what makes monthly budgeting distinct: months are not all the same length. February has 28 or 29 days; January and March have 31. Your rent is the same on the 1st of each, but a month with 31 days gives you three more days of groceries, fuel and coffee than a 28-day month. A monthly budget accounts for that by treating the month as the unit, not a fixed number of days.
It works because the biggest recurring costs in most households are billed monthly: rent or a mortgage payment, electricity and water, internet and mobile, insurance premiums, gym and streaming subscriptions, childcare, and loan or credit-card minimums. When your income is also monthly — a salaried paycheck deposited on the last working day — the whole cycle fits inside one calendar month and the math is a clean subtraction.
Monthly income
Take-home salary and any other money landing inside the calendar month.
Fixed monthly costs
Rent or mortgage, utilities, internet, insurance — the bills tied to the 1st.
Variable monthly spending
Groceries, fuel, dining out, medical — costs that shift day to day across the month.
Month-end remainder
Income minus fixed costs minus variable spending minus savings at month close.
02— The method
How to build a monthly budget in 4 steps
These four steps follow the shape of a calendar month. Enter each amount the way it actually arrives — a monthly rent payment, a weekly grocery run, a daily coffee — and Clear Budget converts every line into its monthly equivalent so the totals stay consistent.
Step 1
Total your monthly income
- Monthly salary (net, after tax)
- Side work or freelance invoiced within the month
- Benefits, child support or rent income paid monthly
Step 2
List fixed monthly obligations
- Housing: rent or mortgage payment
- Utilities: electricity, water, gas, internet, mobile
- Subscriptions: streaming, software, gym, memberships
- Debt minimums: credit card, loan, car finance
Step 3
Estimate variable monthly spending
- Groceries — often a weekly shop, summed to a monthly total
- Transport — fuel, transit passes, parking
- Dining out & entertainment
- Healthcare & household supplies
Step 4
Read your month-end remainder
- Positive — a surplus you can describe, save or carry forward.
- Zero — every unit of income is assigned to a cost or a goal.
- Negative — costs exceed income; the calculator shows the gap plainly.
Month-end remainder = Monthly income − Fixed obligations − Variable spending − Savings
Clear Budget describes and calculates this line; it does not recommend what to do with a surplus or a shortfall. Seeing the number plainly is the point.
03— A worked example
A realistic monthly budget example
Meet Maya. She is salaried and paid monthly on the last working day of each month. Her largest cost is rent, due on the 1st. Here is how a single calendar month breaks down for her — the same shape the calculator produces.
Money in (monthly)
- Net salary (paid monthly)4,200
- Rental income (flatmate)650
- Monthly income total4,850
Fixed obligations (monthly)
- Rent (due 1st)1,600
- Electricity & water140
- Internet & mobile70
- Streaming & gym subscriptions45
- Fixed total1,855
Variable spending (monthly)
- Groceries (weekly shop × 4.3)520
- Transport (fuel + transit)180
- Dining out & entertainment240
- Variable total940
Month-end remainder
Monthly income4,850
− Fixed obligations1,855
− Variable spending940
− Savings (goal)600
Month-end remainder1,455
Maya's month closes with 1,455 left over after rent, utilities, subscriptions, variable spending and her savings goal. That remainder is what the calculator shows her at a glance — a description of where the month landed, not a recommendation to spend or save it.
04— Frequency conversion
Turning weekly and biweekly income into a monthly picture
Not every income or expense is monthly, but your bills are. To compare them honestly you need a monthly equivalent for each non-monthly amount. Clear Budget does this automatically using the average-length month of 365.2425 ÷ 12 ≈ 30.44 days, which keeps conversions consistent across the whole year instead of drifting with 28- or 31-day months.
Weekly → monthly
A weekly amount is multiplied by ~4.348 — a weekly 500 becomes about 2,174 per month.
Biweekly → monthly
A biweekly amount is multiplied by ~2.174 — a biweekly 1,800 becomes about 3,913 per month.
Daily → monthly
A daily amount is multiplied by ~30.44 — a daily 10 becomes about 304 per month.
Annual → monthly
An annual amount is divided by 12 — an annual 1,200 insurance premium becomes 100 per month.
Why a weekly check is not just “× 4”
Four weeks is 28 days, but an average month is about 30.44 days. Multiplying a weekly amount by 4 quietly drops roughly two days of income or spending each month — and over a year that is more than a full month missing. Clear Budget uses the 30.44-day average month so a weekly paycheck and a monthly rent sit on the same scale. If you budget week to week instead, the Weekly Budget Calculator anchors everything to a 7-day cycle; if you are paid every 14 days, the Biweekly Budget Calculator anchors to your real pay schedule.
05— The tool
A monthly budget calculator that does the conversions
Clear Budget is a free monthly budget calculator. Enter your salary, rent, utilities, subscriptions and variable spending the way they actually occur — monthly, weekly or daily — and it converts every line into one consistent monthly picture, plus Daily, Weekly and Annual views. No spreadsheet, no account, no sign-up.
Live monthly totals
Income, fixed costs, variable spending and month-end remainder update as you type.
Private by design
Your numbers stay in your browser. No account, no sign-up, no tracking of your budget.
Multiple currencies
Budget in multiple currencies and switch any time without losing your entries.
06— Questions
Monthly budgeting questions
Why budget by the calendar month instead of every 4 weeks?
My income is weekly, not monthly. Can I still use this?
How do I handle a bill that arrives every two weeks?
What about months with an extra paycheck or a quarterly bonus?
Does Clear Budget tell me how much I should save?
Is my monthly budget saved or sent anywhere?
Ready to build your monthly budget?
Open the free Clear Budget calculator, enter your monthly salary, rent, utilities and spending, and see your month-end remainder instantly — privately, in your own browser.
100% free · No account needed · Private by design