The 50/30/20 Budget Calculator

What the 50/30/20 rule actually means

The rule splits your after-tax income (what actually lands in your bank account, not your salary before deductions) into three buckets: 50% for needs, 30% for wants, and 20% for savings and extra debt payoff.

If your monthly take-home pay is $4,200, that's $2,100 for needs, $1,260 for wants, and $840 for savings. The calculator above does this instantly and shows you the three amounts side by side — often more useful than the percentages alone.

How to use your result

Track a month of real spending first. Sort your last 30 days of transactions into needs, wants, or savings to see your actual split compared to the target.

Look at the gap, not just the numbers. If needs are eating 65% instead of 50%, that's useful information — maybe rent is too high for your income, or a few "needs" are really "wants" in disguise.

Automate the savings piece. Set up an automatic transfer on payday so it happens before you have the chance to spend it elsewhere.

Common mistakes people make

Treating it as a hard rule. In high cost-of-living cities, needs alone can reasonably exceed 50%. Focus on the discipline of tracking, not hitting an exact ratio.

Using gross income instead of take-home pay. Always start from the number that actually hits your bank account.

Forgetting irregular expenses. Car repairs, annual subscriptions, and once-a-year premiums don't show up monthly — build a small buffer for these into your plan.