💰 Finance Calculators
Money decisions reward curiosity. Whether you're shopping for a mortgage, deciding how much to save each month, or stress-testing a retirement plan, a good calculator turns a vague worry into a concrete number you can act on.
The tools below cover the three financial questions most people return to again and again: What will this loan actually cost me? How much could my savings grow if I leave them alone? Will I run out of money in retirement? Every calculator runs in your browser — your inputs never leave the page, no account is required, and the formulas are documented on each page so you can verify the math.
Treat these as decision-support tools, not advice. Real loans include fees and escrow; real returns are not constant; real retirement is messier than any smooth projection. Use the numbers as a sanity check, then talk to a qualified professional before locking in a major decision.
Tools in this category
Loan Calculator
Monthly payment, total interest, and 12-month amortization for any fixed-rate loan.
Compound Interest Calculator
Project investment growth with compound interest and monthly contributions.
Retirement Calculator
Project retirement nest egg and check whether it lasts through life expectancy.
Frequently asked questions
Are these calculators a substitute for financial advice?
No. They use standard formulas and reasonable defaults, but they don't know your tax situation, debt mix, employer benefits, or risk tolerance. Use the output as a starting point for a conversation with a registered advisor or CPA.
Why does the calculated loan payment differ from my mortgage statement?
Lenders typically bundle property tax, homeowners insurance, PMI, and HOA fees into the monthly payment via escrow. The loan calculator only computes principal + interest. Add ~20–30% on top for a realistic all-in housing cost in most US markets.
What return rate should I assume for compound interest?
The S&P 500 has averaged about 10% nominal / 7% real over the last century, but past performance is not a guarantee. For long-horizon planning, 6–7% real is a common conservative assumption; for short horizons, treat market exposure as risky.
Can I trust these for retirement planning?
Use them as a sanity check, not a plan. The retirement calculator assumes a constant return rate, which masks sequence-of-returns risk — a bad first few years of retirement can sink an otherwise viable plan. A Monte Carlo simulator or a flat-fee planner is better for high-stakes decisions.