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Budget Calculator

Turn your take-home pay into a simple spending plan. Enter your monthly after-tax income and choose a rule — the classic 50/30/20 or another split — to see how much to allot to needs, wants and savings. You can also set your own percentages.

Quick examples
$

After taxes and payroll deductions.

Your numbers stay in your browser. Nothing is uploaded.
Needs$2,500.00
Wants
$1,500.00
Savings and debt payoff
$1,000.00
Saved in a year
$12,000.00
Left unassigned
$0.00
Your monthly split
  • Needs
  • Wants
  • Savings

Saved setups

Save a set of inputs you reuse — your usual rate, your loan, your room sizes — and load it back in one tap.

    Your recent calculations

    Results you calculate here are kept on this device so you can come back to them.

      Formula

      Needs = take-home pay × needs %
      Wants = take-home pay × wants %
      Savings and debt payoff = take-home pay × savings %
      50/30/20 rule: 50% needs, 30% wants, 20% savings

      How to use it

      1. Enter your monthly income after taxes and payroll deductions.
      2. Pick a budget rule or choose custom and enter three percentages.
      3. Compare each amount with what you actually spend in that category.

      Worked examples

      $5,000 a month on the 50/30/20 rule

      Needs
      $2,500.00
      Wants
      $1,500.00
      Savings and debt payoff
      $1,000.00
      Saved in a year
      $12,000.00
      Left unassigned
      $0.00

      $3,200 a month on a 70/20/10 split

      Needs
      $2,240.00
      Wants
      $640.00
      Savings and debt payoff
      $320.00
      Saved in a year
      $3,840.00
      Left unassigned
      $0.00

      $4,400 a month with a custom 55/25/15 split

      Needs
      $2,420.00
      Wants
      $1,100.00
      Savings and debt payoff
      $660.00
      Saved in a year
      $7,920.00
      Left unassigned
      $220.00

      What goes in each bucket

      Needs are bills you must pay to live and work: rent or mortgage, utilities, groceries, insurance, transport, childcare and minimum debt payments. Wants are everything optional: eating out, streaming, travel, hobbies and upgrades. Savings covers emergency fund deposits, retirement contributions beyond payroll deductions, investing and any debt payments above the minimum.

      The 50/30/20 rule was popularized by Elizabeth Warren and Amelia Warren Tyagi in the 2005 book All Your Worth.

      When 50/30/20 does not fit

      In expensive cities, needs alone can exceed 50%; a 60/30/10 or 70/20/10 split may be more realistic to start with. Treat the savings share as the one to protect and trim wants first. If retirement contributions already come out of your paycheck, they count toward the savings share even though they are not in your take-home pay.

      Questions people ask

      What is the 50/30/20 rule on $5,000 a month?

      $2,500 for needs, $1,500 for wants and $1,000 for savings and extra debt payments — $12,000 saved in a year.

      How much should I budget on $4,000 a month?

      With 50/30/20: $2,000 for needs, $1,200 for wants and $800 for savings.

      Should I use gross or net income for a budget?

      Net — what actually reaches your bank account. On $3,200 of take-home pay with a 70/20/10 split, that is $2,240 for needs, $640 for wants and $320 for savings.

      Related calculators

      Net Pay CalculatorEstimate take-home pay with your own tax rates.Emergency Fund CalculatorHow big your emergency fund should be and how long it takes to build.Savings Goal CalculatorThe monthly amount to save to hit a target by a deadline.Debt-to-Income (DTI) CalculatorFront-end and back-end DTI the way mortgage lenders measure them.Net Worth CalculatorEverything you own minus everything you owe.Debt Payoff CalculatorSnowball or avalanche: when up to three debts are gone and what they cost.