Solve complex sums in milliseconds
Free, accurate, in-browser calculators across finance, health, academics, and math. No accounts, no paywalls, instant outputs.
Paycheck Calculator
Estimate your take-home pay or net income after federal, state, and local tax withholdings. Toggle hourly vs salary rates.
Mortgage Calculator
Calculate your monthly mortgage payment including principal, interest, taxes, and insurance (PITI). Includes amortization schedule.
Tip Calculator
Quickly calculate the gratuity for a restaurant bill and easily split the total cost among multiple people.
GPA Calculator
Calculate your high school or college grade point average (GPA). Supports weighted grades (AP/IB/Honors) and cumulative semesters.
Grade Calculator
Calculate your current class grade based on weighted categories (exams, quizzes, homework, participation).
BMI Calculator
Calculate your Body Mass Index (BMI) using metric or imperial units and learn your weight status category.
Calorie Calculator (TDEE)
Find your Total Daily Energy Expenditure (TDEE) and calculate calories needed for weight loss, maintenance, or gain.
Age Calculator
Determine your exact age in years, months, weeks, days, hours, and minutes from your birthdate.
Percentage Calculator
Solve percentage problems, including percentage of a value, percentage increase/decrease, and proportion calculations.
Discount / Sale Price Calculator
Calculate the final sale price, total savings, and original price of discounted items during shopping.
Auto Loan Calculator
Calculate monthly car payments, interest costs, and amortization schedules for new or used auto loans.
Personal Loan Calculator
Find your monthly personal loan payments and see a full interest payoff schedule.
Sales Tax Calculator
Calculate sales tax added to a purchase or reverse-calculate the sales tax to find the pre-tax item price.
Compound Interest Calculator
See how your savings grow over time with compound interest. Supports monthly/annual deposits and compounding frequencies.
401(k) / Retirement Savings Calculator
Project your future 401(k) retirement balance based on annual salary, employer matching, and growth rates.
Debt Payoff Calculator
Plan your debt-free timeline using the popular snowball or avalanche debt payoff strategies.
Credit Card Interest Calculator
Find out how long it will take to pay off your credit card balance and how much interest you will accrue.
Weight Loss Goal Calculator
Find the daily calorie deficit required to reach your target weight by a specific date.
Pregnancy Due Date Calculator
Calculate your estimated due date, conception date, and current gestational week/milestones.
Body Fat Percentage Calculator
Estimate your body fat percentage using the US Navy body circumference method.
Water Intake Calculator
Calculate how much water you should drink daily based on your body weight and exercise activity.
BMR Calculator
Calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation to find how many calories your body burns at rest.
Ideal Weight Calculator
Estimate your ideal body weight based on height and sex using the Devine and Robinson clinical formulas.
Body Frame Size Calculator
Determine whether you have a small, medium, or large body frame using the height-to-wrist-circumference ratio method.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio (WHR) and see your World Health Organization cardiovascular risk category.
Heart Rate Zone Calculator
Find your target heart rate training zones for warm-up, fat burn, cardio, and max-effort workouts based on your age.
Ovulation Calculator
Estimate your ovulation date and fertile window based on the first day of your last period and average cycle length.
Conception Date Calculator
Estimate your approximate conception date based on your last menstrual period or your estimated due date.
Child Growth Percentile Calculator
Get a simplified estimate of whether your child's height and weight fall below, at, or above the typical average for their age.
Baby Weight Gain Calculator
Track how much weight your newborn has gained since birth and compare it to typical newborn weight gain rates.
Menstrual Cycle Calculator
Predict your next three period start dates and fertile windows based on your last period and average cycle length.
Pregnancy Weight Gain Calculator
Find your recommended total pregnancy weight gain range based on your pre-pregnancy BMI, using Institute of Medicine guidelines.
Menopause Age Calculator
Get a rough statistical estimate of when you might reach menopause based on average age, genetics, and smoking status.
Final Exam Grade Calculator
Find out what grade you need on your final exam to achieve a target overall grade in your class.
Grade Curve Calculator
Curve test grades and exam scores using common curving methods (Flat Scale, Linear, Root, or Bell Curve).
Date Difference Calculator
Calculate the total number of days, weeks, months, or years between two dates.
Unit Conversion Calculator
Convert between imperial and metric units for length, weight, area, volume, and temperature.
Time Zone Calculator
Convert times between different global time zones and plan virtual meetings easily.
Online Ruler
Turn your phone or computer screen into a ruler. Measure objects in inches and centimeters directly on screen, with optional credit-card calibration for extra accuracy.
Length Converter
Convert length and distance instantly between meters, kilometers, miles, feet, inches, yards, and centimeters.
CM to Inches Converter
Convert centimeters to inches and inches to centimeters instantly with this simple two-way converter.
Weight Converter
Convert weight and mass instantly between kilograms, pounds, ounces, grams, and metric tons.
Temperature Converter
Convert temperatures instantly between Celsius, Fahrenheit, and Kelvin scales.
Volume Converter
Convert volume instantly between liters, gallons, milliliters, cups, fluid ounces, and cubic meters.
Area Converter
Convert area instantly between square meters, square feet, acres, and hectares.
Speed Converter
Convert speed instantly between miles per hour, kilometers per hour, meters per second, and knots.
Pressure Converter
Convert pressure instantly between PSI, bar, pascal, and standard atmospheres.
Force Converter
Convert force instantly between newtons, pound-force, kilogram-force, and dyne.
PPM Calculator
Convert between parts per million (ppm), percent, and ratio concentration values instantly.
Acreage Calculator
Convert acreage between acres, square feet, square meters, and hectares, plus estimate land value per acre.
Currency Converter
Convert between two currencies by entering the current exchange rate manually for an instant calculation.
Time Converter
Convert time instantly between seconds, minutes, hours, days, weeks, and years.
Data Storage Converter
Convert digital storage instantly between bytes, kilobytes, megabytes, gigabytes, and terabytes, with binary and decimal options.
Energy Converter
Convert energy instantly between joules, calories, kilowatt-hours, and BTU.
Angle Converter
Convert angles instantly between degrees, radians, and gradians.
Fuel Economy Converter
Convert fuel economy instantly between miles per gallon (MPG), liters per 100km, and kilometers per liter.
Cooking Measurement Converter
Convert cooking measurements between cups, tablespoons, teaspoons, milliliters, and grams for common ingredients.
Density Converter
Convert density instantly between kilograms per cubic meter, grams per cubic centimeter, and pounds per cubic foot.
Power Converter
Convert power instantly between watts, kilowatts, horsepower, and BTU per hour.
Torque Converter
Convert torque instantly between newton-meters, foot-pounds, and inch-pounds.
Shoe Size Converter
Convert shoe sizes instantly between US, UK, EU, and centimeter sizing standards for men and women.
Clothing Size Converter
Convert clothing sizes instantly between US, UK, and EU letter and number sizing standards.