Smart calculators for everyday life
Mortgage, auto loan, 401(k), BMI, tip, sales tax and more — accurate, instant, and built for the U.S. market.
Featured calculators
Mortgage Calculator
Estimate your monthly mortgage payment, total interest, and total cost for any home loan amount, rate, and term.
finance-calculatorsAuto Loan Calculator
Calculate your monthly car payment, total interest, and total cost for any auto loan — new or used.
finance-calculatorsCompound Interest Calculator
See how savings, a 401(k), IRA, or brokerage account grows with compound interest and monthly contributions.
finance-calculatorsSales Tax Calculator
Calculate U.S. sales tax on any purchase — or work backwards from the total to find the pre-tax amount.
health-and-fitness-calculatorsBMI Calculator
Calculate your Body Mass Index (BMI) from your height and weight in U.S. or metric units.
math-calculatorsPercentage Calculator
Quickly calculate X% of Y, what percentage one number is of another, or the percentage change between two values.
Browse by category
Finance
Mortgage, auto loan, investment, retirement, sales tax, and tip calculators to plan your money decisions.
17 calculatorsHealth & Fitness
Body, nutrition and wellness calculators including BMI, calories and pregnancy planning.
8 calculatorsMath
Percentage, fraction, algebra and general-purpose math calculators for students and engineers.
16 calculatorsDate & Time
Calculate your age, date differences, working days and countdowns.
6 calculatorsConversions
Convert between units of length, weight, temperature, currency and more.
6 calculatorsAuto
Fuel economy, gas trip cost, and car lease calculators for everyday driving and road trips in the U.S.
6 calculatorsConstruction
Concrete, paint, and tile calculators for homeowners and contractors planning projects.
6 calculatorsEducation
GPA, grade, and test score calculators for U.S. students, parents, and teachers.
10 calculatorsCooking
Recipe scaling, kitchen unit conversions, oven temperatures, and food math.
9 calculatorsTravel
Flight time, time zones, currency conversion, and trip planning calculators.
9 calculatorsTech
Bandwidth, file size, hex/binary, password strength, and developer-friendly calculators.
9 calculatorsScience
Physics, chemistry, and engineering calculators for students and pros.
9 calculatorsBusiness
Markup, margin, breakeven, ROI, and small-business math calculators.
9 calculatorsPets
Dog age, cat age, pet food portion, and animal-related calculators.
9 calculatorsReal Estate
Cap rate, rental yield, mortgage affordability, property tax, and house-hacking calculators.
6 calculatorsSports
Running pace, marathon training, cycling speed, swimming pace, and heart rate zone calculators.
6 calculatorsPopular right now
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