All calculators
Every tool on frugalmath, organized by category. Type to filter.
Savings
Savings goal calculator
Time to reach a savings target, or the monthly amount needed.
Emergency fund calculator
Size your fund, then see how inflation and interest move the target.
High-Yield Savings Calculator
Project the interest, then model a rate cut and the tax on it.
CD vs. Savings Calculator
The held-to-term winner, plus the penalty break-even for breaking a CD early.
Sinking Fund Calculator
Split one account across several goals, and get the monthly for each.
Savings Rate Calculator
The share of income you save, and the years to financial independence it buys.
Monthly Savings Calculator
The monthly deposit to hit a goal by a date, and why the rate barely moves it.
Time to First $100k Calculator
How long the first $100,000 takes, and why every $100k after it comes faster.
Car Down Payment Savings Calculator
The monthly amount to save for a car down payment, and the depreciation reason 20% is the target.
Vacation Savings Calculator
Save for each trip cost by its real deadline, not one lump by departure.
Wedding Budget Calculator
Split a budget by category, see which half the guest list moves, and get the real catering cost.
Debt
Credit card minimum payment
How long minimum payments really take, and why the formula decides it.
Debt Avalanche Calculator
Avalanche vs snowball on the same debts, and when the choice barely matters.
Debt Snowball Calculator
What smallest-first costs in interest, and when your first debt disappears.
Loan Amortization Calculator
The payment where principal finally beats interest, and how front-loaded the interest is.
Student Loan Calculator
Standard vs income-driven repayment, with the forgiveness and tax math.
Auto Loan Calculator
Payment and total interest, plus what a dealer rate markup really costs.
Credit Card Payoff Calculator
Pick a payoff date and get the payment, or enter a payment and get the date.
Debt-to-Income Calculator
Front-end and back-end DTI, and the gap between what lenders approve and what's affordable.
Personal Loan Calculator
Payment and total interest, plus the APR you really pay once the origination fee is in.
Debt Consolidation Calculator
Blended rate, the origination-fee break-even, and whether consolidating really saves.
Investing
Compound interest calculator
Future value with compounding, then the real number after inflation and tax.
Dollar-Cost Averaging Calculator
DCA a lump sum or invest it all today, run on identical numbers.
Investment Fee Calculator
What an expense ratio really costs over decades, plus the advisor and plan fees stacked on top.
Index Fund Calculator
Long-horizon growth net of fees, plus the sequence-of-returns risk the smooth line hides.
Rule of 72 Calculator
Years to double your money, the estimate against the exact math, and where the shortcut drifts.
Future Value Calculator
What a lump sum grows to, what it's worth after inflation, and how far the rate assumption moves it.
Annualized Return Calculator
The yearly rate behind a total gain, plus the money-weighted return CAGR gets wrong.
Inflation-Adjusted Return Calculator
Turn a nominal return into a real one, and see what a lump sum buys in today's dollars.
Dividend Reinvestment Calculator
What a DRIP adds over taking dividends in cash, and the tax drag in a taxable account.
Retirement
401(k) Calculator
Project your balance, and see the employer match as the instant return it is.
FIRE number calculator
Your number at 3%, 3.5%, and 4% withdrawal rates, plus the horizon trap.
Roth IRA Calculator
Tax-free growth, plus the honest Roth-vs-Traditional call decided by your tax rate now versus later.
Roth vs Traditional IRA Calculator
The break-even tax rate that decides it, and why return and horizon don't.
Safe Withdrawal Rate Calculator
The safe rate is set by your stock/bond mix, not a universal 4%.
Social Security Claiming Calculator
Break-even age for claiming at 62, 67, or 70, and how investing early checks moves it.
RMD Calculator
Your required withdrawal from the IRS table, and the rate it forces higher every year.
Retirement Savings On Track Calculator
Your savings vs the age-based salary multiples, and the monthly contribution that closes the gap.
Taxes
Federal Tax Bracket Calculator
Your bracket, and the effective rate you actually pay after the math.
Marginal vs. Effective Tax Rate Calculator
Both rates from the bracket math, plus your real next-dollar rate once FICA and state stack on.
Standard vs. Itemized Deduction Calculator
Which deduction wins, the threshold you must clear, and what itemizing saves.
Capital Gains Tax Calculator
Short-term vs long-term, with the gain stacked on your income the way the IRS does it.
After-Tax Income Calculator
Your after-tax income kept separate from take-home pay, with the FICA cap kink shown.
Estimated Tax Payment Calculator
Quarterly tax for the self-employed, sized to the safe-harbor target the IRS actually requires.
Real estate
Mortgage payment calculator
Monthly payment with PMI, and the month PMI actually drops off.
Refinance Calculator
Closing-cost break-even, plus the lifetime interest a lower payment can hide.
Rent vs Buy Calculator
Rent or buy as a net-worth race with the down payment invested, plus the 5% rule check.
Mortgage Payoff Calculator
Interest and years saved by extra payments, and whether prepaying beats investing.
House Affordability Calculator
How much house the 28/36 rule allows, and the gap to what a lender will approve.
Closing Costs Calculator
Estimate the bill, then split true fees from the prepaids you'd owe anyway.
Income & budgeting
Take-Home Pay Calculator
Salary after federal, FICA, and state tax, with the state rate you set.
Hourly to Annual Salary Calculator
Convert an hourly wage to a salary, plus the true hourly rate after paid time off.
Salary to Hourly Calculator
Convert a salary to an hourly rate, plus your real rate after the hours you actually work.
Overtime Pay Calculator
Time and a half or double time, plus whether you're owed overtime at all.
Freelance Hourly Rate Calculator
The gross rate to charge for a target take-home, after self-employment tax.