Money Scenario Explorer
Take your monthly surplus and explore what happens if you go different routes — paying off debt, investing, saving for something, or just living your life. See the 5, 10, and 25-year picture for each path.
Monthly Surplus
Your leftover money after all expenses — use the Budget Optimizer to find this number
What if you paid off your debt?
Pick a debt — credit card, student loan, car note — and put extra money at it. See when you'd be free and exactly how much interest you'd avoid.
What if you built an emergency fund?
A 3–6 month safety net changes how job loss, a car repair, or a medical bill hits you. See how fast you'd get there.
What if you invested in the S&P 500?
Boring and consistent. Monthly contributions into an index fund, left alone. Compound interest starts slow — then it absolutely doesn't.
Using 7% avg. annual real return (historical S&P 500 average, inflation-adjusted)
What if you saved toward a specific goal?
House down payment, a new car, a trip, a business. Give it a name and a number — see exactly when you'd cross the finish line.
What if you just spent it?
Travel. Experiences. Good food. Treating people you care about. There's no compound interest on memories, but they're also real. Zero judgment here.
Enter your monthly surplus above, then fill in any scenarios to see where you could end up.
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What Each Scenario Calculates
The debt payoff calculator uses your balance, interest rate, and monthly payment to show when you'd be debt-free and how much interest you avoid — works for credit card debt, student loans, and car loans. The emergency fund calculator shows how long to reach a 3-month or 6-month safety net, using a 4.5% high-yield savings account (HYSA) rate.
The S&P 500 compound growth calculator projects monthly contributions at 7% average annual real return (the historical inflation-adjusted average) out to 30 years. The chart makes compound interest visible — the gap between what you put in and what you end up with widens dramatically over time. The savings goal calculatortells you exactly when you'd hit a target like a house down payment, a car, or a vacation fund.
Should You Invest or Pay Off Debt First?
One of the most common personal finance questions is whether to invest spare money or use it to eliminate debt. The math depends on interest rates: if your debt costs more than ~7% annually (most credit cards charge 20%+), paying it off first usually wins. If your rate is lower — a subsidized student loan or a 0% car note — investing in a broad index fund often comes out ahead over a long horizon.
This tool lets you run both scenarios side by side and compare the 5, 10, and 25-year outcomes. All math runs in your browser — nothing is stored or shared. Not sure what your monthly surplus is? Calculate it with the Budget Optimizer first.
Disclaimer: The results produced by this tool are for general educational and illustrative purposes only. They do not constitute financial advice and should not be relied upon when making investment, debt management, or savings decisions. All projections use simplified assumptions (fixed interest rates, consistent monthly contributions, no taxes or fees) and will not reflect your actual financial outcomes. Past market performance is not a guarantee of future results. If you need personalised guidance, consult a qualified financial adviser.