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Monthly budget calculator (50/30/20 rule)

A monthly budget splits net income into clear buckets so you know how much you can spend and how much to set aside. This tool applies the 50/30/20 rule (or the beginner-friendly 70/20/10 alternative) instantly.

Quick answer (calculator defaults)

With net income $10,000 and the 50/30/20 rule:

  • Needs (50%): $5,000
  • Wants (30%): $3,000
  • Savings & investing (20%): $2,000/month → $24,000/year

What this tool calculates

  • Monthly caps for needs, wants, and savings
  • Side-by-side 50/30/20 vs 70/20/10
  • Annual savings if you keep the savings percentage
  • Educational guidance only (not personalized financial advice)

Currency is just a label: use USD, GTQ, or another unit. The math is percent of net income.

Allocation formula

Monthly allocation

Needs = net_income × (needs% / 100) Wants = net_income × (wants% / 100) Savings = net_income × (savings% / 100) Annual savings ≈ monthly savings × 12

Worked example (defaults)

Inputs: net income $10,000 · method 50/30/20

  1. Needs = 10,000 × 0.50 = $5,000
  2. Wants = 10,000 × 0.30 = $3,000
  3. Savings = 10,000 × 0.20 = $2,000
  4. Annual savings = 2,000 × 12 = $24,000

Same income with 70/20/10: needs $7,000, wants $2,000, savings $1,000 (annual $12,000). Better when fixed costs already exceed 50%.

Scenario tables (same engine logic)

Amounts rounded to 2 decimals like the calculator.

50/30/20 rule

Net incomeNeeds (50%)Wants (30%)Savings (20%)Annual savings
$5,000$2,500.00$1,500.00$1,000.00$12,000.00
$7,500$3,750.00$2,250.00$1,500.00$18,000.00
$10,000$5,000.00$3,000.00$2,000.00$24,000.00
$12,000$6,000.00$3,600.00$2,400.00$28,800.00
$15,000$7,500.00$4,500.00$3,000.00$36,000.00
$20,000$10,000.00$6,000.00$4,000.00$48,000.00

70/20/10 rule (same incomes)

Net incomeNeeds (70%)Wants (20%)Savings (10%)Annual savings
$5,000$3,500.00$1,000.00$500.00$6,000.00
$10,000$7,000.00$2,000.00$1,000.00$12,000.00
$15,000$10,500.00$3,000.00$1,500.00$18,000.00
$20,000$14,000.00$4,000.00$2,000.00$24,000.00

What goes in each bucket

CategoryTypical examples50/30/20 %
NeedsRent/mortgage, basic groceries, utilities, commute, minimum insurance, minimum debt payments50%
WantsDining out, streaming, hobbies, non-essential shopping, entertainment30%
Savings & investingEmergency fund, goals, investments, extra principal on debt20%

Housing and net income

  • A common housing guide is about 30% of net income for rent/mortgage (inside the needs bucket).
  • Always budget from net pay (after taxes and payroll deductions), not gross.
  • If rent + utilities already crush the 50% needs cap, try 70/20/10 before dropping savings entirely.

Habits that make the budget stick

  1. Track spending for 1–2 weeks to calibrate real categories.
  2. Automate savings on payday (pay yourself first).
  3. Review weekly: not only at month-end.
  4. Adjust the method if fixed costs are high; don’t quit tracking.
  5. Pair with debt payoff and debt-to-income ratio when credit is heavy.
Disclaimer

This calculator is educational. It is not personalized financial, tax, or legal advice. Percentages are starting points: dependents, high housing costs, or expensive debt may require a different split.

FAQ

Allocate 50% of net income to needs, 30% to wants, and 20% to savings and investing (or extra debt payments). It’s a starting framework, not a law.

With 50/30/20: $2,000/month and $24,000/year. With 70/20/10: $1,000/month and $12,000/year.

When fixed costs (housing, transport, basics) regularly exceed 50% of net income. 70/20/10 gives needs more room while still reserving 10% for savings.

Use net (take-home). Gross overstates every bucket and hides taxes and contributions.

Contractual minimums usually sit in needs. Extra principal payments belong in the savings/debt 20% (or 10% under 70/20/10).

This page is a full monthly budget planner with method comparison. For the classic split only, also try the 50/30/20 rule calculator.

A frequent guide is up to ~30% of net income. Adjust for your city and protect the savings line whenever you can.

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