Calculate exact age from date of birth in years, months, days, total days lived, day of birth, and next birthday countdown.

Create a live countdown to any future date or measure time since a past event in days, hours, minutes, and seconds.

Calculate days, weeks, months, years, business days, weekend days, and total hours between two dates.

Calculate percentages, percentage increase or decrease, percentage difference, discounts, markups, and X percent of any number.

Calculate sale price, discount amount, savings percentage, and final price for shopping, invoices, pricing, and promotions.

Estimate fuel needed and trip cost using distance, mileage, fuel efficiency, local fuel price, round trips, and passenger sharing.

Estimate fixed-rate loan payments, fee-adjusted borrowing costs, payoff timing, amortization, and extra-payment savings.

Calculate how long it may take to pay off credit card debt, total interest, total paid, and savings from extra monthly payments.

Calculate your debt-to-income ratio from gross monthly income, rent or mortgage, credit cards, loans, and other monthly debt payments.

Calculate how much to save each month to reach a savings goal, estimate time to goal, progress, and projected balance.

Estimate retirement savings, monthly income, employer match, inflation-adjusted purchasing power, withdrawal runway, and the contribution needed to reach your target.

Estimate certificate of deposit interest and maturity value, compare CD offers with savings accounts, and model taxes, penalties, reinvestment, and CD ladders.

Calculate inflation-adjusted value, future buying power, cumulative inflation, and price change over time.

Calculate a car loan EMI with flat or reducing interest, synced down payment, trade-in, fees, balloon payment, affordability, and amortization.

Compare leasing versus buying a car with financing, equity, resale, mileage, insurance, maintenance, fees, and break-even analysis.

Calculate a home down payment, loan amount, monthly mortgage, PMI, closing costs, affordability, and 10%, 20%, or 30% down payment comparisons.

Calculate loan payments and generate a full amortization schedule with principal, interest, remaining balance, extra payments, and CSV export.

Compare renting and buying a home with mortgage, rent growth, taxes, insurance, maintenance, equity, and investment assumptions.

Calculate return on investment, net gain or loss, total investment, annualized ROI, and return multiple online.

Calculate personal net worth with detailed asset fields, liability fields, custom entries, and debt ratio insights.

Calculate break-even units, break-even revenue, contribution margin, and the sales volume needed to cover business costs.

Calculate gross profit, operating profit, net profit, margins, markup, tax, and return on cost from business revenue and expenses.

Estimate your pregnancy due date, current week, approximate month, trimester, and milestones using LMP, conception, or ultrasound dating.

Estimate income tax, taxable income, average tax rate, annual take-home pay, and monthly take-home income.

Calculate sales tax, before-tax price, tax amount, and final price online with add and remove tax modes.

Add VAT to a net price or remove included VAT from a gross price with a custom rate and clear net, VAT, and gross totals.

Estimate 2025 or 2026 federal withholding, FICA, state and local tax, deductions, take-home pay, and employer payroll cost.

Estimate metabolic age, BMR, BMI, daily energy needs, and waist-to-height context from age, gender, height, weight, and activity level.

Calculate daily calorie needs for weight loss, maintenance, or weight gain with BMR, TDEE, BMI, and macro estimates.

Estimate ideal body weight with the Devine formula, calculate adjusted body weight, and compare BMI-based reference values in kg or pounds.

Estimate a daily beverage-fluid goal from weight, activity, climate, sex, and pregnancy or breastfeeding context, then track glasses locally.

Compare a 2026 Health FSA carryover with a grace period, estimate unused funds at risk, and plan your spending and claim deadlines.

Estimate projected lease mileage, excess miles, and a possible end-of-lease overage charge using your contract's mileage allowance and per-mile rate.

Compare a mortgage recast with keeping your payment unchanged after a lump-sum principal payment. Estimate payment reduction, payoff time, and interest savings.

Estimate monthly mortgage payments, taxes, insurance, PMI, payoff time, and total interest with an amortization schedule and extra-payment comparison.

Estimate five heart rate training zones and your Zone 2 BPM range using age-based or Karvonen heart-rate reserve methods.

Estimate BMI-based pregnancy weight gain ranges for one baby or twins and track weekly progress privately in your browser.

Estimate your next period, ovulation date, fertile window, PMS timing, and cycle pattern with a private browser-based menstrual cycle tracker.

Estimate blood alcohol concentration, elimination time, and US BAC reference levels from weight, drink size, ABV, quantity, and drinking time.

Calculate risk-based forex and gold lot size, pip value, margin, risk amount, take-profit targets, and combined position exposure.

Calculate markup, gross margin, profit, reverse selling price, tax-inclusive pricing, pricing tiers, and batch product results.

Calculate stock profit or loss after commissions, taxes, charges, multiple purchase lots, break-even price, targets, and portfolio positions.

Estimate annual, monthly, and quarterly US property tax using state averages or a local millage rate, assessment ratio, exemptions, and escrow costs.

Calculate a rent increase by amount or percentage, compare affordability and inflation, review selected regional caps, and project future rent.

Calculate square footage for multiple rooms and shapes, convert area units, deduct excluded space, and estimate flooring, tile, carpet, or paint costs.

Estimate interior or exterior paint, primer, gallons, liters, smart can sizes, and project cost for multiple rooms with door and window deductions.

Calculate tiles, boxes, waste, grout, thinset, underlayment, labor, and total flooring cost for multiple rooms and layout patterns.

Solve missing proportion values, check and simplify ratios, handle direct, inverse, continued, and compound proportions, and split quantities proportionally.

Calculate employee hours from clock-in and clock-out times, subtract unpaid breaks, estimate overtime and gross pay, and export a weekly timesheet.

Factor whole numbers and polynomials, find prime factors and factor pairs, calculate GCF and LCM, and practice with step-by-step checks.

Estimate boat loan payments, total interest, taxes and fees, insurance, storage costs, extra-payment savings, and a month-by-month amortization schedule.

Calculate the time difference between two times or dates in hours, minutes, and seconds. Compare multiple intervals, subtract breaks, count business days, or add and subtract a duration.

Define a piecewise function with interval conditions, evaluate values, view a graph and table, inspect boundaries, and calculate symbolic derivatives or numerical integrals.

Estimate home equity, available HELOC capacity, draw-period interest-only payments, repayment payments, rate-change impact, and a month-by-month balance schedule.