Personal Finance · Interactive Tools
Money basics
Before a single dollar is invested, five foundations decide whether investing is even possible: know where your money goes, keep a buffer so surprises don't become debt, put numbers and dates on your goals, track the one figure that sums it all up — and clear the debt whose interest outruns any market. Work through the tabs in order, or jump to the one you need.
A simple starting framework: aim for roughly 50% of take-home pay on needs, 30% on wants, and 20% to saving and extra debt payoff. Enter your numbers to see how your split compares.
Your plan vs. 50/30/20
- Needs
- Wants
- Save & invest
You're clearing the 20% bar — that surplus is exactly what funds investing. Send it somewhere automatic so it never sits idle. The 50/30/20 split is a starting guideline, not a rule — adjust it to your life.
The foundations, briefly
- The 50/30/20 budget. Roughly half of take-home pay on needs, a third on wants, a fifth to saving and debt. The percentages are a guideline, not a law — what matters is that the split is deliberate, and that the save-and-invest slice is automatic. Money you never see is money you don't spend.
- The emergency fund. Months of expenses in boring, instant cash, sized to how steady your income is. It's not an investment — it's the insurance that keeps a car repair from becoming a 25% credit-card balance, and it's what lets the invested money stay invested through a bad month.
- The savings goal. A goal with a number and a date becomes a monthly amount; growth carries part of the load for far-away goals and almost none for near ones — which is why short-term money belongs in cash, not stocks.
- Net worth. Assets minus debts: the single number that captures the whole picture. Income is how fast you're moving; net worth is where you actually are. Tracking it beats tracking any account alone.
- Debt payoff. High-interest debt is a guaranteed negative return — clearing a 22% card beats any bet the market offers except an employer match. Avalanche (highest rate first) wins on the spreadsheet; snowball (smallest balance first) wins on momentum; the one you stick with wins in real life. And if a rate looks extreme, ask first whether refinancing can lower it.
Once the foundations hold, the next question is where each new dollar should go — the Next Dollar tool ranks it. Educational only, not financial advice.
Sources & further reading
How this tool was made
Pure arithmetic on the numbers you type, computed in your browser and never sent anywhere. These five tools use no market data, no forecasts, and no historical returns — the only rate involved is the growth assumption you set yourself on the savings-goal and net-worth tabs.
Educational use only, not financial advice. Every figure traces back to the sources above or to the inputs you set — the full method and the source code are public.