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Financial
Loans, mortgages, interest, savings and everyday money math.
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Fitness & Health
Body metrics and everyday health estimates.
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Math
Equations, statistics, and general-purpose math tools.
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Construction
Estimate materials, volumes and quantities for projects.
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Everyday & Conversions
Age, time, dates, temperature and unit conversions.
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Science & Space
Astronomy, sleep and fun science calculators.
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Text & Code
Encoders, converters and text utilities.
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Financial
Loan Calculator Open tool Loan Calculator Monthly payment, total interest, and a full amortization schedule. Compound Interest Calculator Open tool Compound Interest Calculator See how savings grow with compound interest and monthly contributions. Simple Interest Calculator Open tool Simple Interest Calculator Calculate simple interest and total repayment on a principal. Discount Calculator Open tool Discount Calculator Find the sale price and how much you save from a percentage discount. Sales Tax Calculator Open tool Sales Tax Calculator Add sales tax to a price to get the tax amount and final total. Tip Calculator Open tool Tip Calculator Calculate the tip, total, and amount per person when splitting a bill. Mortgage Calculator Open tool Mortgage Calculator Estimate your full monthly mortgage payment including principal, interest, taxes and insurance. Retirement Calculator Open tool Retirement Calculator Project your retirement savings from your current age, contributions and expected return. Auto Loan Calculator Open tool Auto Loan Calculator Estimate your monthly car payment with down payment, trade-in, sales tax and APR. Debt Payoff Calculator Open tool Debt Payoff Calculator See how long to pay off a credit card or loan, total interest, and the power of extra payments.
Fitness & Health
BMI Calculator Open tool BMI Calculator Body Mass Index from height and weight, metric or imperial. Calorie (TDEE) Calculator Open tool Calorie (TDEE) Calculator Estimate your BMR and daily calorie needs using the Mifflin-St Jeor equation. Due Date Calculator Open tool Due Date Calculator Estimate your pregnancy due date, current week and trimester from your last period. Body Fat Calculator Open tool Body Fat Calculator Estimate your body fat percentage using the U.S. Navy circumference method. One Rep Max Calculator Open tool One Rep Max Calculator Estimate your one-rep max from a lift and see training weights for every percentage. Running Pace Calculator Open tool Running Pace Calculator Find your pace per mile and per km, plus speed, from a distance and finish time. Ideal Weight Calculator Open tool Ideal Weight Calculator Estimate your ideal body weight using the Devine, Robinson and Hamwi formulas.
Math
Construction
Concrete Calculator Open tool Concrete Calculator Cubic yards, pre-mixed bags, and cost for a concrete slab. Paint Calculator Open tool Paint Calculator Estimate how many gallons of paint you need from room size and coats. Tile Calculator Open tool Tile Calculator Work out how many tiles and boxes you need for a floor or wall. Square Footage Calculator Open tool Square Footage Calculator Calculate the square footage of a room or lot and estimate material or flooring cost. Gravel Calculator Open tool Gravel Calculator Estimate the gravel needed for a driveway or area in cubic yards, tons and cost.
Everyday & Conversions
Age Calculator Open tool Age Calculator Find your exact age in years, months, days — plus total weeks, days and hours. Time Duration Calculator Open tool Time Duration Calculator Calculate the exact duration between two dates and times. Work Hours Calculator Open tool Work Hours Calculator Add up worked hours from a start and end time, minus breaks, in decimal and HH:MM. Temperature Converter Open tool Temperature Converter Convert instantly between Celsius, Fahrenheit and Kelvin. Length Converter Open tool Length Converter Convert between millimeters, centimeters, meters, kilometers, inches, feet, yards and miles. Weight Converter Open tool Weight Converter Convert between kilograms, grams, pounds, ounces, stone and tonnes. Date Calculator Open tool Date Calculator Find the days between two dates, or add and subtract days, weeks, months and years. Fuel Cost Calculator Open tool Fuel Cost Calculator Estimate the fuel cost and gallons for a trip from distance, MPG and gas price. Speed Converter Open tool Speed Converter Convert between miles per hour, kilometers per hour, meters per second, knots and feet per second. GPA Calculator Open tool GPA Calculator Calculate your grade point average from letter grades and credit hours. Cooking Converter Open tool Cooking Converter Convert recipe amounts between cups, grams, milliliters and spoons by ingredient. Area Converter Open tool Area Converter Convert area between square feet, meters, yards, acres, hectares and more.
Science & Space
Sleep Calculator Open tool Sleep Calculator Find the best bedtime or wake-up time based on 90-minute sleep cycles. Weight on Planets Open tool Weight on Planets See how much you would weigh on the Moon, Mars, Jupiter and every other planet. Age on Planets Open tool Age on Planets Find out how old you are on Mercury, Mars, Jupiter and beyond, based on orbital years.