Budget Calculator
See exactly where your money goes each month and check your spending against the classic 50/30/20 budget rule.
Enter your monthly income and list your expenses by type — needs, wants, or savings. The calculator shows your surplus or deficit and grades each bucket against the 50/30/20 rule so you can see instantly what is on track.
Monthly Expenses
How to use this calculator
- Step 1: Enter your monthly take-home income.
- Step 2: Add your expenses, giving each a name, amount, and type: Needs, Wants, or Savings.
- Step 3: Use the + Add expense button for as many rows as you need, and remove any you do not want.
- Step 4: Click Calculate to see your monthly surplus or deficit.
- Step 5: Read the 50/30/20 breakdown to see which buckets are on track and which need work.
The formula
Needs % = needs / income × 100; Wants % = wants / income × 100; Savings % = savings / income × 100; Surplus = income − total expenses
Worked example
With $6,000 of monthly income and $3,200 in needs, $1,900 in wants, and $900 in savings, the calculator reports needs at 53.3% (off track, over the 50% target), wants at 31.7% (off track, over 30%), savings at 15.0% (off track, below 20%), and a surplus of $0.00. Moving $300 from wants to savings would fix two buckets at once.
Frequently Asked Questions
What is the 50/30/20 budget rule?
The 50/30/20 rule says to spend roughly 50% of after-tax income on needs (housing, groceries, bills), 30% on wants (dining out, entertainment), and put at least 20% toward savings and debt payoff. It was popularized by Elizabeth Warren in the book All Your Worth as a simple framework anyone can check against. It is a guideline, not a law — high-cost cities often push needs above 50%.
What counts as a need versus a want?
Needs are expenses you cannot reasonably avoid: rent or mortgage, utilities, groceries, insurance, transportation, and minimum debt payments. Wants are spending that improves your life but is optional: dining out, subscriptions, hobbies, vacations. Savings includes emergency-fund contributions, retirement investing, and extra debt payments above the minimum.
What should I do if my needs are over 50%?
First, make sure nothing is miscategorized — a pricey grocery habit may belong partly in wants. If needs are genuinely over 50%, the two levers are cutting the biggest needs (housing, car) or raising income, because trimming small wants rarely closes a large gap. The calculator shows exactly which bucket is off track so you know where to focus.
How often should I redo my budget?
Review it monthly, since income, subscriptions, and bills change more often than people realize. Many people run it once when something changes — a raise, a move, a new loan — and again a month later to confirm the plan held. A quick monthly check takes five minutes and catches subscription creep before it becomes a deficit.
Is this budget calculator free to use?
Yes, completely free with no signup. Everything runs in your browser, so none of your income or expense numbers are sent anywhere. Run as many budgets as you like — for example, compare your current spending against a proposed one with lower housing costs.