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Budget Calculator

Allocate exactly 100% of monthly income, compare non-negative actual spending, expose fixed-dollar extras, and review transparent balances and planning ratios.

Use this result well

Inputs that matter
Positive monthly income, category percentages totaling exactly 100%, non-negative actual spending, optional fixed-dollar extra categories, emergency-fund balance, and monthly debt payment
Output to expect
Planned and actual category amounts, planned balance after extras, actual surplus/shortfall, savings rate, 50/30/20 comparison, transparent planning ratios, chart, and CSV
How it works
Percent categories allocate exactly 100% of income; fixed-dollar extras remain visible on top, while actual totals and raw ratios are direct arithmetic without a proprietary health score
  • Custom percentage totals are rejected unless they equal 100%; extra fixed-dollar categories can create a clearly displayed planned overage.
  • Emergency-fund coverage and debt-payment share are planning context, not a credit score, lender DTI, or personalized financial recommendation.

Choose your path

Built around the job you need to finish

Build a monthly plan that reconciles to income, compare it with non-negative actual spending, and expose raw planning ratios without a proprietary health score.

First-budget household

Start from a complete 50/30/20 allocation and see actual surplus or shortfall.

Enter take-home income and actual spending, then review group comparison and category variances.

Can reconcile every planned and actual dollar and treats 50/30/20 as a starting framework.

Custom-envelope planner

Use custom percentages and extra fixed-dollar categories without hidden normalization.

Set percentages to exactly 100%, add named extras, and inspect the planned balance warning.

Sees and corrects an over-allocated plan rather than receiving silently rescaled categories.

Mobile monthly reviewer

Update actuals and export a readable snapshot on a phone.

Edit spending, inspect surplus and raw optional context, then copy/share/export CSV.

Inputs and actions remain named/tap-sized and no invented score obscures the raw numbers.

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Reference & details

How it works

50/30/20 Rule

A popular budgeting framework: 50% for needs (housing, utilities, groceries), 30% for wants (entertainment, dining), 20% for savings and debt repayment.

Needs = Income × 0.50 | Wants = Income × 0.30 | Savings = Income × 0.20

Zero-Based Budgeting

Every dollar of income is assigned a purpose. Total allocated expenses plus savings must equal total income.

Income = Sum of All Category Allocations

Planned and actual reconciliation

Custom percentage categories must total exactly 100% and are never silently normalized. Fixed-dollar extras remain visible on top, so an over-allocated plan produces a signed planned-balance warning.

Planned Balance = Income − Percentage Plan − Fixed-Dollar Extras

Updated: August 2026

Example Scenarios

Applying the 50/30/20 rule to a take-home pay of $5,500 per month.

Net Income: $5,500Rule: 50/30/20

Needs: $2,750, Wants: $1,650, Savings: $1,100

A renter in an expensive city adjusts the rule to allocate more to housing and savings.

Net Income: $7,200Needs: 40%Wants: 25%Savings: 35%

Needs: $2,880, Wants: $1,800, Savings: $2,520

A household adds a fixed-dollar category on top of a 100% plan and sees the exact planned overage instead of hidden normalization.

Common Mistakes to Avoid

Budgeting gross income instead of net

Budget from take-home pay after taxes and deductions. A $75K salary may net $55K — budgeting on $75K leads to overspending by ~$1,600/month.

Treating the 50/30/20 rule as rigid

The rule is a starting framework, not a universal target. Adjust categories to actual obligations and priorities while keeping the full plan reconciled to income.

FAQ

The displayed totals directly reconcile the values entered. The 50/30/20 split is only a planning framework, and optional emergency-fund/debt ratios are context rather than a credit or financial-health assessment.

Yes, our Budget Calculator is completely free with no registration required. There are no usage limits, hidden fees, or account setup — just open the tool and calculate.

Yes, the Budget Calculator is fully responsive and works on all devices including phones, tablets, and desktops. All calculations run in your browser for fast, private results.

It supports a 50/30/20 starting plan or exact custom percentages, actual category spending, fixed-dollar extras, planned and actual balances, raw context ratios, charts, copy/share, print, and CSV export.

Yes. Change one category or actual amount at a time and watch the signed balances. Custom percentages must still total exactly 100%, while extra fixed-dollar categories remain separately visible.

About Budget Calculator

Create and audit a monthly plan locally in your browser. The tool reports direct arithmetic and raw optional ratios; it does not issue a proprietary financial-health score.