Math, finance, health, and everyday tools - with real formulas, detailed results, and a clean interface.
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Calculate payments and total interest for amortized loans, deferred payment loans, and bonds.
Calculate monthly payments, total interest, and full amortization for your car loan.
Calculate boat loan payments, interest, tax, upfront cost, and a full amortization schedule.
See how extra or biweekly payments save interest and shorten your mortgage term.
Find sales commission from price and rate, or use the tiered commission calculator.
Find gross margin, profit, revenue, or cost from any two values, with markup shown.
Find markup, cost, revenue, or profit from any two values, with the profit margin shown.
See how long it takes to pay off a card balance, or the payment needed to clear it in time.
Estimate your monthly payment, VA funding fee, loan amount, total interest, and amortization.
Estimate your monthly payment, upfront and annual mortgage insurance (MIP), and total interest.
Analyze cash flow, cap rate, cash-on-cash return, IRR, and total profit on a rental investment.
Find your available equity and estimate monthly payments on a home equity loan.
Estimate your home equity line of credit payments during draw and repayment periods.
Calculate tax amounts and reverse-calculate pre-tax prices from any US state rate.
Calculate present value, future value, and total interest for annuities.
Estimate annuity payout amounts for a fixed term or how long a fixed payout will last.
Project investment growth with compound interest and regular contributions.
Calculate return on investment (ROI) and annualized ROI from your invested and returned amounts.
Find simple interest and end balance, or solve for principal, rate, or term, with a full schedule.
Time value of money solver: find FV, PV, payment, interest rate, or number of periods.
See how your savings grow from deposits and contributions with compound interest.
Estimate your monthly car lease payment and compare leasing to buying the same vehicle.
Convert any salary to hourly, weekly, monthly, and annual equivalent pay rates.
See your new pay and raise amount per hour, week, month, and year from a percent or dollar raise.
Convert an annual, monthly, weekly, or daily salary into an hourly wage, and back.
Calculate break-even point and savings from refinancing your mortgage.
Calculate the equivalent purchasing power of money across any years using U.S. CPI data from 1913 to 2024.
Get your full amortization schedule with monthly payment, total interest, and year-by-year breakdown.
Calculate your monthly loan payment for any term, or find out how long to pay off a loan with fixed payments.
Find the payment to repay a loan over a fixed term, or how long a fixed payment takes to clear it.
Calculate compound interest growth with contributions, tax, and inflation adjustments.
Find your debt-free date using the avalanche method. Model extra monthly, yearly, or one-time payments.
Compare your current debts to a consolidation loan. See monthly savings and total interest saved.
Estimate your actual paycheck after federal income tax, Social Security, Medicare, state tax, and deductions.
Find out how much you need to retire, how much to save, and how long your money will last.
Compare Roth IRA growth vs. a taxable account. See projected balance, taxes saved, and year-by-year schedule.
Calculate monthly payments, total interest, payoff date, and real APR for any personal loan.
Calculate business loan payments, total interest, real APR, and full amortization schedule.
See how much house you can afford based on your income and debts, or a fixed monthly budget.
Find the home price your cash supports, the cash needed to buy, or your down payment percentage.
Estimate payments, total interest, and payoff time, plan extra payments, and project your balance after graduation.
Plan your personal budget with income and expenses to see your net surplus or deficit, DTI ratio, and spending breakdown.
See how much monthly rent you can afford based on your income and existing debt payments.
Find the sale price after a percent-off or fixed-amount-off discount and how much you save.
Find the sale price, discount, or original price from any two values, with optional sales tax.
Find the sale price, savings, original price, or discount rate from any two values.
Compare the retirement value of a Traditional IRA, Roth IRA, and a taxable account.
Find the internal rate of return (IRR) from a fixed or irregular series of cash flows.
Estimate your 2025 or 2026 federal income tax refund or amount owed.
Find the present value of a future sum or a series of periodic deposits.
Find a bond's price, yield, or coupon, plus dirty price and accrued interest.
Compare a lump sum against monthly pension income, and find your break-even age.
Convert an interest rate between compounding periods, from annual (APY) to continuous.
Find the annual percentage yield from a rate and compounding frequency, plus final balance.
See what an investment will grow to from a starting amount, rate, and periodic deposits.
Project your 401(k) balance at retirement, with employer match and early withdrawal costs.
Calculate your body fat percentage, category, lean mass, fat mass, and ideal body fat for your age.
Calculate your Body Mass Index, BMI Prime, category, and healthy weight range.
Estimate calories burned in over 100 activities from your body weight and duration.
Convert your step count into calories burned from your weight, height, and walking pace.
Estimate calories burned walking or on a treadmill from your weight, pace, distance, and slope.
Convert steps to kilometers (and back) from your height, sex, or a measured stride length.
Find your BMR with the Harris-Benedict equation, plus daily calorie needs by activity level.
Find your ideal exercise heart rate zones from your age, using the Karvonen method.
Estimate your 1RM from a submaximal set with the Epley, Brzycki, and Lombardi formulas.
Estimate body fat with the 2023 Army one-site tape method and check AR 600-9 standards.
Find your daily calorie needs based on BMR and activity level using Mifflin-St Jeor.
Estimate your Total Daily Energy Expenditure and calorie targets for weight loss or gain.
Find the calories to maintain your weight from BMR and activity, with a macro breakdown.
Find the daily deficit and target intake to reach your goal weight by a target date.
Find the daily calories and surplus you need to gain weight and reach your goal.
Find your daily protein, carb, and fat targets in grams for your goal.
See how many grams of carbs to eat daily at 40%, 55%, 65%, and 75% of calories.
Estimate your recommended daily protein intake from your body metrics and activity.
Estimate your Basal Metabolic Rate and daily calorie needs by activity level.
Estimate your ideal body weight from the Robinson, Miller, Devine, and Hamwi formulas.
Find your female body shape and waist-hip ratio from bust, waist, high hip, and hip measurements.
Estimate your bra size from bust and band measurements, with US, UK, EU, and other regional sizes.
Calculate exact age in years, months, days, hours, minutes, and seconds.
Predict a child's adult height or check height percentile using CDC data.
Find your due date, gestational age, trimester, and full week-by-week pregnancy schedule.
Estimate your most fertile days, ovulation date, fertile window, and due date if pregnant.
Predict your next periods and most probable ovulation days for the next 6 cycles.
Estimate your pregnancy due date from your last period, ultrasound, conception, or IVF date.
Find the days you are most likely to conceive, plus your ovulation window and due date.
Estimate when a baby was conceived from a due date, last period, or ultrasound.
Find your recommended pregnancy weight range and weekly weight-gain schedule by BMI.
Find a percentage of a number, percentage difference, and percentage change.
Find the percentage increase or decrease between an initial and final value.
Find the percent decrease between an initial and final value, with the drop and steps.
Find the percent change (increase or decrease) between an initial and final value, with steps.
Find the percentage difference between two numbers from the absolute difference and their average.
Add, subtract, multiply, or divide fractions with step-by-step solutions.
Solve A:B = C:D, simplify a ratio, convert to 1:n and a percentage, and scale ratios.
Find population or sample standard deviation, variance, and mean with steps.
Get count, sum, mean, median, mode, range, variance, and standard deviation of a data set.
Find the weighted average of a five-star rating from the number of 1 to 5-star votes.
Find the odds of dice rolls — sums, matching values, at least/at most, and D&D advantage.
Find the odds of getting a number of heads in any number of coin flips, fair or biased.
Find a z-score from a raw score, convert between z-scores and probabilities, and get the area between two z-scores.
Find Z, t, chi-square, and F critical values for one- and two-tailed tests, with the rejection region.
Solve sides, angles, area, and perimeter of a right triangle from any two values.
Find sin, cos, tan, cot, sec, and csc of any angle, and solve a right triangle.
Find the distance between two points on a 2D plane, in 3D space, or by latitude and longitude.
Solve a² + b² = c² from any two sides, with exact radical answers, angles, area, and steps.
Find the hypotenuse of a right triangle from two legs, a leg and an angle, area, or the hypotenuse.
Find the slope, angle, grade, distance, and equation y = mx + b from two points or a point and a slope.
Write a line's equation from a point and a slope, in point-slope, slope-intercept, and standard form.
Find the equation y = mx + b from two points or a slope and a point, with the slope and intercepts.
Convert a quadratic between standard and vertex form, with the vertex, zeros, and a parabola graph.
Add, subtract, and multiply matrices, plus transpose, power, determinant, and inverse.
Find the nth term and sum of arithmetic, geometric, and Fibonacci sequences.
Round a number to whole numbers, decimals, a fraction, or significant figures, with 9 modes.
Round any number to the nearest thousand, ten thousand, and hundred thousand.
Solve any triangle from 3 values: sides, angles, area, heights, medians, and more.
Find a triangle's area from base & height, two sides & an angle, three sides, or two angles & a side.
Volume of a sphere, cone, cube, cylinder, tank, capsule, frustum, ellipsoid, and more.
Find the volume and surface area of a triangular prism from the base triangle and length.
Surface area of a sphere, cone, cube, cylinder, tank, capsule, frustum, ellipsoid, and more.
Area of a rectangle, triangle, trapezoid, circle, sector, ellipse, or parallelogram, in any unit.
Perimeter of a square, rectangle, triangle, circle, ellipse, polygon, and more, in any unit.
Calculate your GPA or find the grade needed to reach your target GPA.
Find your percentage score and letter grade from the questions and wrong or right answers.
Find probabilities of two events, a series of events, or a normal distribution.
Find the confidence interval and margin of error for a population mean from your sample.
Add, subtract, multiply, and divide binary numbers, and convert between binary and decimal.
Add, subtract, multiply, and divide hex numbers, and convert between hex and decimal.
Convert a decimal number to two's complement binary and back, for any bit length.
Find a circle's radius, diameter, circumference, and area from any one known value.
Split a length into the golden ratio φ ≈ 1.618 — enter one part to get the other two.
Find a regular hexagon's area, perimeter, diagonals, and radii from any one value.
Find the area of a circle from its radius, diameter, or circumference using A = πr².
Find the circumference, radius, diameter, and area of a circle from any one value.
Find arc length from the radius and central angle, plus sector area and chord length.
Solve for the result, base, or exponent of a power expression, with steps.
Find the square root of any number as a decimal and in simplified radical form, plus both roots.
Average two or more percentages, with an optional weighted average by sample size.
Compute log₂(x) from x, or solve for x from log₂(x), using the change-of-base formula.
Find the GCF of two or more numbers with step-by-step prime factorization.
List all factors of a number, with factor pairs, the count, and prime factorization.
Find the quotient and remainder when one number is divided by another.
Find the mean, median, mode, range, geometric mean, sum, and count of a data set.
Find the average (mean) of a list of numbers, plus sum, count, median, min, max, and range.
Add up weekly work hours from clock-in/out times, deduct breaks, and calculate pay with overtime.
Find the number of hours and minutes between two times or between two full dates.
Find the duration between two times or add/subtract time from a start time.
Add, subtract, multiply, or divide time values in days, hours, minutes, seconds.
Calculate running pace, speed, or finish time for any race distance.
Find the number of days between two dates, or add and subtract from any date.
Find the number of years between a BC year and an AD year, minding the missing year zero.
Count days between two dates, broken down into weekends, holidays, and business days.
Find your Korean age, international age, and year age from your birth date or birth year.
Estimate the heating and cooling BTUs needed for a room or house.
Estimate an appliance's energy usage and running cost per day, week, month, and year.
Find average velocity from distance and time, final velocity from acceleration, or a weighted average.
Solve Newton's law F = G·m₁·m₂/r² for the force, either mass, or the distance between two objects.
Solve gravitational potential energy PE = m·g·h for energy, mass, height, or gravity.
Solve KE = ½·m·v² for the kinetic energy, mass, or velocity of a moving object.
Find the protons, neutrons, electrons, atomic number, mass number, and charge of an atom.
Convert between grams, moles, and molar mass with n = m / M, or from a chemical formula.
Convert milligrams to milliliters (and back) using density or medication concentration.
Convert grams to cups (and back) for 20 common ingredients like flour, sugar, butter, and water.
Name the interval between two notes, or find the note an interval above or below a root.
Find network address, broadcast address, usable hosts, and more from any IP/CIDR.
Estimate how long a download or upload takes from the file size and your internet speed.
Convert Minecraft items to stacks and back, with the inventory slots and chests needed.
Generate a pixel-perfect block circle from any diameter, with the grid and total block count.
Calculate trip fuel cost and required fuel for any distance, efficiency, and gas price.
Find your MPG, L/100 km, and cost per mile from two odometer readings and a fill-up.
Find average speed, distance, or time from any two values, in km/h, mph, m/s, or knots.
Calculate dew point, relative humidity, or air temperature. Also shows absolute humidity and comfort level.
Estimate the wet-bulb temperature from air temperature and relative humidity (Stull formula).
Find density, mass, or volume with the formula density = mass / volume and many unit options.
Find how many helium balloons it takes to lift a person or object, by balloon size and gas.
Find the velocity, distance, and time of a falling object from the time or the height.
Convert between mass, molar mass, moles, and number of molecules from any two values.
Find the time of flight, range, and maximum height from launch speed, angle, and height.
Solve Q = m·c·ΔT for heat energy, mass, temperature change, or specific heat capacity.
Solve pV = nRT for pressure, volume, amount of substance, or temperature, with flexible units.
Solve λ = v/f for wavelength, wave speed, or frequency, with presets for light and sound.
Estimate your blood alcohol content from your weight, time, and the drinks you consumed.
Find when to go to bed or wake up so you rise between sleep cycles feeling refreshed.
Estimate roof area from base area and pitch, plus the shingles, roll roofing, and felt needed.
Find the roof pitch angle, percentage, and x:12 ratio, plus rafter length, from rise and run.
Estimate concrete volume, weight, and bags for slabs, footings, columns, curbs, and stairs.
Find a pipe's internal volume and the mass of liquid inside, in metric and imperial units.
Find the board feet and cost of lumber from its thickness, width, length, and quantity.
Estimate the gravel needed to cover an area by volume and weight, plus the total cost.
Find the steps, riser height, tread run, stringer size, and angle for a staircase.
Find the square footage of a room, lot, or surface in nine shapes, with quantity and cost.
Find how many tiles and boxes you need for a floor or wall, with grout gap and cost.
Find your course handicap and compute your WHS handicap index from your rounds.
Find a team's win percentage from wins, losses, and ties (ties count as half a win).
Find a cricket batter's strike rate from runs scored and balls faced, or solve in reverse.
Decode a tire code into diameter, width, and revolutions per mile, and compare two tire sizes.