How This 50/30/20 Budget Calculator Works
The 50/30/20 rule divides your after-tax income into three buckets: about 50% for needs, 30% for wants, and 20% for savings and extra debt repayment. It was popularized by Senator Elizabeth Warren and Amelia Warren Tyagi in All Your Worth, and it endures because it is simple enough to actually follow — one split, three buckets, done in seconds.
What goes in each bucket matters more than the percentages. Needs are the things you truly cannot skip: rent or mortgage, groceries, utilities, transport, insurance, and minimum debt payments. Wants are the nice-to-haves: dining out, streaming, hobbies, travel, upgrades. Savings and debt is everything future-facing: emergency fund, retirement, investing, and any debt payment above the minimum. Note the boundary: only the minimum payment counts as a need — extra payoff money belongs in the 20% bucket.
needs = income × 0.50 • wants = income × 0.30 • savings & debt = income × 0.20
Yearly amounts are each monthly amount × 12. Use take-home pay — what lands in your bank account after tax and deductions.
Worked example: $5,000 of monthly take-home pay. Needs get $5,000 × 0.50 = $2,500 a month ($30,000 a year); wants get $5,000 × 0.30 = $1,500 a month ($18,000 a year); savings and debt get $5,000 × 0.20 = $1,000 a month ($12,000 a year). $2,500 + $1,500 + $1,000 = $5,000 — the three buckets always add back up to 100% of income.
Practical tips
If savings leave your account on payday, you never have to decide to save. The 20% line is the one to protect when the other two run over.
Rent or mortgage dominates the needs bucket. In high-cost areas, needs above 50% are common — adjust the split to reality rather than abandoning savings entirely.
If $300 already goes to a 401(k) straight from your paycheck, your additional savings target from take-home pay drops accordingly — do not double-count it.
The rule runs on after-tax income. Running it on gross salary overstates every bucket and makes the targets impossible.
Paying more than the minimum on a loan is a savings-bucket move. That distinction is what makes the 20% bucket do double duty: wealth-building and debt freedom.