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How Much House Can You Afford?
GuideThe 28/36 rule, down payments and hidden costs — what a lender really looks at, in plain English.
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Finance
Loans, interest, pay and everyday money math.
Work out the monthly payment, total interest and total cost of any loan, with a full amortization schedule.
Open →Estimate your full monthly mortgage payment — principal, interest, property tax, home insurance, PMI and HOA — with total interest and an amortization schedule.
Open →Estimate your annual and monthly property tax from a home's value and your local rate, with assessment ratio, exemptions and your effective tax rate.
Open →Project your Traditional IRA at retirement and its after-tax value, with tax-deferred growth, your contributions and the up-front tax your pre-tax contributions save.
Open →Find the compound annual growth rate between a beginning and ending value over a number of years, plus the total return and total gain.
Open →Convert a nominal interest rate into its annual percentage yield (APY) for any compounding frequency, and see the interest earned on a balance over time.
Open →Project dividend income from a yield and optional annual growth, with monthly and annual payouts and a DRIP reinvestment option that compounds your balance.
Open →Find your FIRE number and how many years to financial independence from your expenses, savings, contributions, return and safe withdrawal rate.
Open →Find how much you can borrow against your home — your equity, available credit at a given CLTV, and the monthly payment on a home equity loan or HELOC.
Open →Estimate your monthly private mortgage insurance, when it drops off, and the total PMI you'll pay before reaching 20% equity.
Open →See how much interest and time you save by paying your mortgage every two weeks instead of monthly — the biweekly payment, years shaved off and interest saved.
Open →See how savings or investments grow over time with compound interest and regular contributions.
Open →Find the present and future value of an annuity — regular payments at a fixed rate, ordinary or annuity due, with total interest and a growth chart.
Open →Estimate how long it takes to double your money at a given return — or the rate needed to double in a set time.
Open →Convert an annual salary to an hourly, weekly or monthly rate — and back again.
Open →Convert an hourly wage to a yearly, monthly and weekly salary based on your hours and weeks worked.
Open →Calculate the tip and split the bill evenly between any number of people.
Open →See if refinancing saves money and how fast you break even on closing costs.
Open →Project your retirement nest egg from savings, monthly contributions and returns.
Open →Estimate your 401(k) balance at retirement including employer matching and growth.
Open →Calculate this year's Required Minimum Distribution from your IRA or 401(k) using the IRS Uniform Lifetime Table.
Open →Project your tax-free Roth IRA balance at retirement and see how much tax you save versus a taxable account.
Open →See your 2026 HSA contribution limit, the federal, state and FICA tax you save each year, and how your health savings account grows when invested.
Open →Project your 529 plan's value by the time your child starts college and see how much of the four-year cost it covers.
Open →Estimate federal and state tax on your investment profit, with 2025 long-term and short-term rates by filing status.
Open →Find how long it takes to clear credit card debt and the total interest you'll pay.
Open →Compare snowball and avalanche strategies to pay off multiple debts faster.
Open →See if rolling your debts into one loan lowers your monthly payment and interest — enter each balance and rate, then a new loan rate and term to compare.
Open →Work out your student loan payment, payoff date and total interest — including interest capitalized during school and grace, plus what paying extra saves.
Open →Calculate return on investment, net profit and annualized ROI for any investment.
Open →Analyze a rental property's monthly cash flow, cash-on-cash return, cap rate and DSCR from the price, financing and rent.
Open →Find the monthly deposit needed to reach a savings goal by your target date.
Open →Calculate the maturity value and APY of a certificate of deposit from your deposit, term length and interest rate — see exactly what it grows to.
Open →Calculate simple interest and the total owed or earned on a principal over time.
Open →Estimate how much house you can afford from income, debts and down payment.
Open →Compare the long-run net worth of renting vs buying a home — with the break-even year, using the opportunity-cost (invest-the-difference) method.
Open →See how much of a bonus you take home after US withholding — the 22% flat federal rate, Social Security, Medicare and state — using 2026 IRS Publication 15 rates.
Open →Find out if moving a credit-card balance to a 0% promo card saves money after the transfer fee — interest both ways, payoff time and the payment that clears it within the promo.
Open →See whether buying discount points is worth it — the cost of points, monthly savings, the break-even month and your net result over the years you keep the loan.
Open →See how inflation changes the buying power of money over a number of years.
Open →Add or remove US sales tax from a price and see the tax amount and total.
Open →Add or remove VAT at any rate to find net price, VAT amount and gross total.
Open →Estimate your US federal income tax, effective rate and take-home pay by filing status.
Open →Work out your US self-employment (SECA) tax from net profit — the Social Security and Medicare split, the deductible half and your effective rate.
Open →Estimate your take-home pay per paycheck after taxes, FICA and retirement contributions.
Open →Add up your assets and liabilities to see your total net worth, and understand your financial position at a glance with a clear breakdown.
Open →Estimate how much life insurance your family needs with the DIME method — income replacement, debts, mortgage, education and final expenses, minus what you already have.
Open →Calculate your debt-to-income ratio to see how lenders view your finances.
Open →Work out your down payment amount and loan amount from a home price and percentage.
Open →Calculate your loan-to-value ratio from a property value and down payment, and see if PMI applies.
Open →Split your monthly income into needs, wants and savings with the 50/30/20 rule.
Open →Find the true APR of a loan including fees, convert a monthly interest rate to APR, and see APR vs APY — free, with worked examples.
Open →Work out how much to save for an emergency fund based on your monthly expenses.
Open →See how much rent you can afford based on your income and the 30% rule, with a comfortable monthly range so you don't overstretch your budget.
Open →Calculate your overtime pay and total weekly earnings from your hourly rate.
Open →Add up your weekly work hours from clock-in and clock-out times, with breaks, overtime and gross pay.
Open →Auto
Car loans, leases and payment math.
Calculate your monthly car payment including taxes, fees, trade-in and down payment.
Open →Find the car price you can afford from a monthly payment budget, down payment, trade-in, APR and loan term.
Open →Estimate your monthly car lease payment from price, residual value and money factor.
Open →Estimate the fuel needed and total cost of a trip from distance, efficiency and price.
Open →Calculate mileage reimbursement from the miles you drove and the rate per mile, using the IRS standard rate or your own custom cents-per-mile rate.
Open →Compare the total cost of leasing versus buying a car over the same period.
Open →Business
Pricing, margins and break-even.
Calculate profit margin, markup percentage and selling price from cost and revenue.
Open →Calculate commission earned and total pay from your sales and commission rate.
Open →Build a year-by-year depreciation schedule using straight-line, declining balance or MACRS — first-year deduction, accumulated depreciation and book value.
Open →Find how many units you must sell to cover your fixed and variable costs, plus the revenue and contribution margin at your break-even point.
Open →Calculate the sale price and the amount you save after a percentage discount — enter the original price and the percent off to see both.
Open →Health
Body metrics and daily energy needs.
Calculate your Body Mass Index in metric or imperial units and see your weight category.
Open →Estimate your daily calorie needs (BMR and TDEE) for maintaining, losing or gaining weight.
Open →Estimate your blood alcohol content from your weight, sex, number of drinks and time using the Widmark formula.
Open →See your recommended pregnancy weight gain by pre-pregnancy BMI (IOM guidelines), with a healthy target for your current week.
Open →Estimate your body fat percentage using the US Navy tape-measurement method.
Open →Calculate the calories your body burns at rest using the Mifflin-St Jeor equation.
Open →Estimate your ideal body weight using the Devine, Robinson, Miller and Hamwi formulas.
Open →Split your daily calories into protein, carb and fat targets for your goal.
Open →Find your most fertile days and next period from your last cycle and length.
Open →Estimate your baby's due date and current pregnancy week from your last period.
Open →Estimate your one-rep max and training percentages from a set's weight and reps.
Open →Estimate how much water you should drink each day based on weight and activity.
Open →Work out your running pace, speed and finish time from distance and time.
Open →Estimate calories burned during exercise from activity, weight and duration.
Open →Find the best bedtime or wake-up time based on 90-minute sleep cycles, so you wake at the end of a cycle feeling refreshed instead of groggy.
Open →Work out your target heart-rate training zones — warm-up, fat-burn, aerobic and peak — from your age and resting heart rate, using the max-HR and Karvonen methods.
Open →Date & Time
Count days, spans and deadlines.
Count the days, weeks and months between two dates — or how long until a future date.
Open →Calculate exact age in years, months and days between a birth date and any date.
Open →Count down the days, weeks and months until any upcoming date or event — or count up the time that has passed since a date in the past.
Open →Count working days between two dates, excluding weekends and chosen holidays.
Open →Calculate the hours and minutes between two times, ideal for timesheets and shifts.
Open →Add or subtract days, weeks, months or years from any date to find the new date.
Open →Math
Percentages and quick number tools.
Find a percentage of a number, percentage change, and what percent one number is of another.
Open →Calculate your grade point average from your course grades and credit hours on the standard 4.0 scale, with your total quality points.
Open →Find your weighted course grade from assignment scores and weights, or the score you need on the final to hit your target.
Open →Add, subtract, multiply and divide fractions with simplified results and decimals.
Open →Calculate mean, variance and standard deviation for a data set (sample or population).
Open →Convert numbers to Roman numerals and Roman numerals back to numbers instantly.
Open →Simplify a ratio to its lowest terms or solve a proportion for the missing value, with the equivalent decimal and percentage shown too.
Open →Find the mean, median, mode, range and sum of any set of numbers at once — just paste your values and get every average instantly.
Open →Compare products by price per unit and see which one is the better deal, plus how much you save.
Open →Find the hypotenuse or a missing leg of a right triangle with a² + b² = c².
Open →Find the distance, midpoint and slope between two points on a coordinate plane.
Open →Solve any quadratic equation ax² + bx + c = 0 for real or complex roots, with the discriminant and the step-by-step quadratic formula.
Open →Find the least common multiple and greatest common divisor of two or more numbers.
Open →Convert numbers to and from scientific notation and see the expanded form.
Open →Calculate permutations (nPr), combinations (nCr) and factorials for any n and r, with the formulas and exact results — ideal for probability and stats.
Open →Count the ways to partition n objects into k groups (Stirling numbers of the second kind) and into any number of groups (Bell number).
Open →Break a number into its prime factors, list all its divisors, and check whether it is prime.
Open →Write any number in words — including decimals and a cheque-style amount for USD.
Open →Conversions
Units and currencies, converted instantly.
Convert length, weight, temperature and volume between metric and imperial units.
Open →Convert between world currencies with a simple, fast exchange-rate calculator.
Open →Convert fuel economy between US MPG, UK MPG, km/L and liters per 100 km — compare car efficiency across different measurement systems.
Open →Convert cooking volumes between cups, tablespoons, teaspoons, milliliters and ounces.
Open →Convert oven settings between Celsius, Fahrenheit and UK gas marks, with the fan (convection) equivalent.
Open →Convert temperatures between Celsius, Fahrenheit and Kelvin instantly, with the formulas and a table of common temperatures for each scale.
Open →Convert speed between mph, km/h, m/s, knots and feet per second instantly, with a clear table of common values for each unit.
Open →Convert digital storage between bytes, KB, MB, GB, TB and PB, using both decimal (1000) and binary (1024) values, instantly and for free.
Open →Convert height between centimeters, meters, and feet and inches — perfect for forms, fitness and comparing metric and imperial heights.
Open →Convert weight between kilograms, pounds, stones, ounces and grams instantly, with a reference table of common conversions for each unit.
Open →Convert numbers between binary, octal, decimal and hexadecimal, and see each value side by side — a handy free tool for programming and CS homework.
Open →Convert length between meters, feet, miles, inches, kilometers, yards and centimeters instantly, with a table of common conversions.
Open →Convert volume between liters, gallons, milliliters, cups, pints and quarts.
Open →Convert area between square feet, square meters, acres, hectares and more.
Open →Home & DIY
Room, paint and material estimates.
Estimate how many gallons of paint you need for a room based on wall area.
Open →Calculate area in square feet for rooms and projects, plus total material cost.
Open →Work out what any appliance costs to run — per day, month and year — from its wattage and your electricity rate.
Open →Estimate how many solar panels you need, the system size and cost, and the payback period — worked back from your power bill, with the 30% tax credit.
Open →Turn your floor-to-floor rise into a buildable staircase — number of steps, riser height, total run and stringer length, with code checks.
Open →Estimate how many drywall sheets you need for a room's walls and ceiling, plus joint compound, tape, screws and cost — with waste included.
Open →Work out how much insulation you need — R-value to add, layer thickness, number of rolls, batts or bags, and the material cost, with waste included.
Open →Estimate the concrete you need for a slab in cubic yards, cubic feet and bags.
Open →Estimate how many tiles and boxes you need for a floor or wall, with waste.
Open →Estimate the gravel, mulch, sand or soil you need for a project in cubic yards, cubic feet and tons — from the area and depth you enter.
Open →Estimate the BTUs needed to cool or heat a room from its square footage, adjusted for sunlight, occupancy and climate, to size an AC or heater.
Open →Work out the flooring area and number of boxes you need, including waste.
Open →Estimate your roof's surface area from its footprint and pitch, then the roofing squares, shingle bundles, underlayment and cost you need — waste included.
Open →Work out how many deck boards, joists and screws you need for your deck size, board width and joist spacing — waste and cost included.
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