How to use the finance tools
Money questions tend to come in a sequence. How much can I save? How long until I'm out of debt? Is this loan any good? Should I put cash in a Roth or a traditional account? The calculators above follow that order, so you can work through a real plan instead of one-off numbers.
A good starting point is your net worth. Add what you own, subtract what you owe, and write the figure down. Do it again in three months. The direction matters more than the size.
Next, tackle debt. The credit card payoff tool shows how much interest a minimum payment really costs, which is often a shock. The snowball versus avalanche visualizer then compares two payoff orders on your actual balances. Avalanche saves more interest. Snowball gives quicker wins. Pick the one you'll stick with.
Saving and investing
Compound interest is the engine behind every long-term plan. Move the sliders and watch how starting five years earlier can beat doubling your monthly deposit later. The FIRE calculator turns that into a target number and a timeline, and the savings-rate view shows how fast the timeline shrinks if you save a little more.
The dollar-cost averaging tool compares steady monthly buying against a lump sum, using assumptions you control. It's an illustration, not a forecast. Real markets won't follow a tidy curve.
Inflation quietly eats everything. The inflation impact calculator shows what today's cash buys in twenty years, so you don't confuse a flat balance with safety.
Loans, mortgages and taxes
For borrowing, the loan calculator gives your monthly payment and total interest. The mortgage tool adds PMI, escrow and prepayments, with a full amortization table you can export to CSV. The payoff strategy calculator shows what an extra payment each month saves.
The Roth versus traditional comparator uses federal brackets and an optional state rate to compare after-tax results. Break-even and ROI calculators round out the set for business decisions.
Everything here runs in your browser, and your inputs are not sent anywhere. These tools give estimates. They don't replace advice from a licensed professional who knows your full situation.
A habit of checking before you commit
Before you sign a loan, open a savings account or take on a big expense, run the numbers twice. Once with the offer as stated, and once with something worse: a higher rate, a lower return, a month of lost income. If the plan survives the bad version, it's sturdy.
A 20,000 car loan at 5 percent over five years costs about 377 a month and 2,600 in interest. Stretch it to seven years to lower the payment and you pay roughly 3,700 in interest. The monthly figure fell, the real cost rose. A calculator shows that in a second, and a sales desk may not.
Small gaps, big differences
Savers underestimate time. Putting away 300 a month at 6 percent for 30 years gives about 300,000 from 108,000 of deposits. Waiting ten years and starting at 20 years out gives roughly 140,000. Same monthly amount, less than half the result.
Borrowers underestimate fees. A mortgage with a rate a quarter point lower but 3,000 more in closing costs only wins if you stay long enough to earn that back. Do the break-even before you celebrate the rate.
Taxes are the third trap. A pre-tax number and a take-home number are different animals, so check which one a tool is giving you.
What the tools can't know
They don't know your lender's exact fees, your tax bracket after deductions, or your own job risk. They give you the shape of the answer. For big decisions, take that shape to a licensed adviser or your lender and ask them to fill in the rest. Your numbers stay in your browser while you experiment.