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Budget Calculator — 50/30/20 Rule

See how your spending maps to the 50/30/20 rule — and where to adjust.

Updated June 2026 · Editorial standards

Your income

$

Needs (target: 50%)

$
$
$
$
$
$

Wants (target: 30%)

$
$
$
$
$

Savings & debt (target: 20%)

$
$
$
Surplus
$1,250
Needs· $2,550
51%
Wants· $550
11%
Savings· $650
13%

Your needs are 51% of income (target 50%), wants 11% (target 30%), and savings 13% (target 20%).You have $1,250/month unallocated — consider moving it to savings or investments.

Budget split

Savings health

Below targetAhead
On track13% of income

You save $650/month — the 50/30/20 target is $1,000. You're at or above the 20% target — great.

50/30/20 breakdown

CategoryTargetYour %AmountGap
Needs50%51%$2,550+$50
Wants30%11%$550-$950
Savings & debt20%13%$650+-$350
By the KalkWise Editorial Team Reviewed for accuracy Updated June 2026

What is the budget calculator?

In short

The 50/30/20 rule splits your after-tax income into three buckets: 50% to needs (housing, food, utilities), 30% to wants (dining, entertainment, shopping), and 20% to savings and debt repayment. It is a simple framework for sustainable spending without detailed line-by-line budgeting.

This budget calculator categorises your monthly spending into needs, wants, and savings, compares each category against the 50/30/20 targets, and shows where you're over or under budget. A donut chart and comparison table make the gaps visual.

How to use this calculator

  1. 1Enter your monthly after-tax income.
  2. 2Fill in your actual spending in each needs category.
  3. 3Fill in your wants spending.
  4. 4Enter your monthly savings, investments, and extra debt payments.
  5. 5Review the donut chart and comparison table to find where to adjust.

The formula

Needs≤50%×income
Wants≤30%×income
Savings≥20%×income
Target needs = income × 0.50, wants = income × 0.30, savings = income × 0.20. The gap for each category is actual spending minus the target.
I
— Monthly after-tax income
N
— Monthly needs spending (housing, food, utilities, etc.)
W
— Monthly wants spending (dining, entertainment, etc.)
S
— Monthly savings + debt repayments

Worked example

The scenario

Monthly income: $5,000. Needs: $2,200 (44%), Wants: $550 (11%), Savings: $750 (15%). Unallocated: $500.

gives

The result

Needs are under the 50% target — great. Savings at 15% are below the 20% target. Consider moving $250 of the $500 unallocated into savings to hit 20%.

Common use cases

  • Building a first budget without over-complicating it
  • Identifying whether overspending is in needs or wants
  • Deciding how much more to save for a specific goal
  • Sharing a clear budget summary with a partner

Limitations & assumptions

  • 50/30/20 is a guide, not a rule — high-cost cities may force needs above 50%.
  • Income should be after-tax; use the Salary Calculator to find this.
  • Does not account for irregular expenses like car repairs or medical bills.

Frequently asked questions

The framework was popularised by US Senator Elizabeth Warren and her daughter Amelia Warren Tyagi in their 2005 book 'All Your Worth'.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.