Free Online Calculators
Fast, accurate calculators for every need. No signup required — just run the numbers.
100+Calculators
15Languages
1500+Pages
100%Free
🏃 Fitness & Health
- BMI CalculatorCalculate your Body Mass Index (BMI) instantly
- Calorie CalculatorCalculate your daily calorie needs based on age, gender, weight, height, and activity level using the Mifflin-St Jeor equation
- Running Pace CalculatorCalculate your running pace per km or mile
- Body Fat CalculatorEstimate your body fat percentage using the U
- Ideal Weight CalculatorFind your ideal body weight using multiple formulas (Devine, Robinson, Miller, Hamwi)
- Heart Rate Zone CalculatorCalculate your target heart rate zones for training
- Pregnancy Due Date CalculatorCalculate your estimated due date based on the first day of your last menstrual period (LMP)
- Water Intake CalculatorCalculate how much water you should drink daily based on your weight and activity level
- One Rep Max CalculatorCalculate your estimated one-rep max (1RM) for any lift using the Epley formula
- Protein Intake CalculatorCalculate how much protein you need daily based on your weight, goal, and activity level
- BMR CalculatorCalculate your Basal Metabolic Rate (BMR) to find how many calories your body burns at rest
- TDEE CalculatorCalculate your Total Daily Energy Expenditure based on activity level
- Macro CalculatorCalculate your daily macronutrient needs (protein, carbs, fat) based on your goals
- Blood Alcohol CalculatorEstimate your Blood Alcohol Concentration (BAC) based on drinks, weight, and time
- Sleep CalculatorFind the best time to sleep or wake up based on sleep cycles of 90 minutes
- Steps to Calories CalculatorEstimate calories burned from walking based on steps, weight, and pace
- Ovulation CalculatorEstimate your most fertile days and ovulation date based on your menstrual cycle
- Waist to Hip Ratio CalculatorCalculate your waist-to-hip ratio to assess health risk related to body fat distribution
- Lean Body Mass CalculatorCalculate your lean body mass (total weight minus body fat)
- Blood Pressure CalculatorCheck your blood pressure reading and understand what your systolic and diastolic numbers mean
- Due Date CalculatorCalculate your estimated due date based on your last menstrual period or conception date
- Pregnancy Weight Gain CalculatorCalculate recommended weight gain during pregnancy based on your pre-pregnancy BMI and current week of pregnancy
🔢 Math
- Percentage CalculatorCalculate percentages easily
- Fraction CalculatorAdd, subtract, multiply, and divide fractions
- Square Root CalculatorCalculate the square root of any number instantly
- Standard Deviation CalculatorCalculate standard deviation, variance, mean, and more for any data set
- Scientific Notation CalculatorConvert numbers to and from scientific notation
- Logarithm CalculatorCalculate logarithms with any base
- Hex to Decimal ConverterConvert hexadecimal to decimal and decimal to hexadecimal
- GPA CalculatorCalculate your Grade Point Average
- Speed Distance Time CalculatorCalculate speed, distance, or time
- Triangle CalculatorCalculate area, perimeter, and angles of a triangle given sides or dimensions
- Volume CalculatorCalculate the volume of common 3D shapes: cube, sphere, cylinder, and cone
- Area CalculatorCalculate the area of common shapes: rectangle, circle, triangle, and trapezoid
- Random Number GeneratorGenerate random numbers within a range
- Quadratic Formula CalculatorSolve quadratic equations (ax² + bx + c = 0) and find roots using the quadratic formula
- Ratio CalculatorSolve ratio proportions and find missing values
- Exponent CalculatorCalculate powers and exponents
- Mean Median Mode CalculatorCalculate mean, median, mode, range, and other statistics for any data set
- Prime Number CheckerCheck if a number is prime and find its factors
- Scientific CalculatorFree online scientific calculator with trigonometric, logarithmic, and exponential functions
- Matrix CalculatorCalculate matrix determinant, inverse, transpose, and multiplication
- Percentage Change CalculatorCalculate the percentage increase or decrease between two values
💰 Finance
- Compound Interest CalculatorCalculate compound interest on savings or investments
- Mortgage CalculatorCalculate your monthly mortgage payment, total interest, and amortization
- Loan CalculatorCalculate monthly payments for any loan
- Tip CalculatorCalculate tip amount and split the bill
- Salary CalculatorConvert between hourly, weekly, monthly, and annual salary
- ROI CalculatorCalculate Return on Investment (ROI)
- Discount CalculatorCalculate sale prices and savings
- Auto Loan CalculatorCalculate monthly car payments, total interest, and total cost of an auto loan
- Investment CalculatorCalculate future value of investments with regular contributions and compound interest
- Retirement CalculatorCalculate how much you need to save for retirement and estimate your retirement income
- Income Tax CalculatorEstimate your federal income tax based on US tax brackets for 2024
- Sales Tax CalculatorCalculate sales tax amount and total price including tax
- Inflation CalculatorCalculate the impact of inflation on purchasing power over time
- Debt Payoff CalculatorCalculate how long to pay off debt and how much interest you will pay
- Net Worth CalculatorCalculate your net worth by adding up assets and subtracting liabilities
- Mortgage Payment CalculatorCalculate your monthly mortgage payment including principal and interest
- Paycheck CalculatorEstimate your take-home pay after federal and state taxes, Social Security, and Medicare deductions from your gross salary
📅 Date & Time
- Age CalculatorCalculate your exact age in years, months, days, hours, and minutes
- Date Difference CalculatorCalculate the number of days, weeks, months, and years between two dates
- Time Zone ConverterConvert time between time zones
- Days Until CalculatorCalculate how many days until a specific date
- Time Duration CalculatorCalculate the duration between two times or add/subtract hours, minutes, and seconds from a time
- Weeks CalculatorCalculate the number of weeks between two dates or find a date a certain number of weeks from now
📏 Conversions
- Km to Miles ConverterConvert kilometers to miles and miles to kilometers instantly
- Kg to Lbs ConverterConvert kilograms to pounds and pounds to kilograms
- Celsius to Fahrenheit ConverterConvert temperatures between Celsius, Fahrenheit, and Kelvin
- CM to Inches ConverterConvert centimeters to inches and inches to centimeters
- Liters to Gallons ConverterConvert liters to gallons (US and UK) and gallons to liters instantly
- Shoe Size ConverterConvert shoe sizes between US, EU, UK, and CM measurements
- Binary to Decimal ConverterConvert binary numbers to decimal and decimal to binary instantly
- MPH to KPH ConverterConvert miles per hour to kilometers per hour and vice versa
- Ounces to Grams ConverterConvert ounces to grams and grams to ounces instantly
- Feet to Meters ConverterConvert feet to meters and meters to feet
- Square Meters to Square Feet ConverterConvert square meters to square feet and vice versa
📊 Construction
- Concrete CalculatorCalculate how much concrete you need in cubic yards or bags for your project
- Paint CalculatorEstimate how much paint you need based on room dimensions and number of coats
- Concrete Block CalculatorCalculate how many concrete blocks or cinder blocks you need for a wall
- Mulch CalculatorCalculate how much mulch you need in cubic yards or bags
- Wallpaper CalculatorCalculate how many rolls of wallpaper you need for a room
📊 Everyday
- Hours CalculatorCalculate total hours worked between start and end times, with break deduction
- Grade CalculatorCalculate your weighted average grade from multiple assignments and their weights
- Dog Age CalculatorConvert your dogs age to human years using the latest scientific research
- Gas Mileage CalculatorCalculate your fuel efficiency in MPG or L/100km and estimate fuel costs
- Electricity Cost CalculatorCalculate how much an appliance costs to run based on wattage and usage hours
- Cat Age CalculatorConvert your cats age to human years
- Bra Size CalculatorFind your correct bra size by entering your band and bust measurements
- Ring Size CalculatorFind your ring size from finger circumference or diameter
- Love CalculatorFun love compatibility calculator! Enter two names and see your love match percentage
- Word CounterCount words, characters, sentences, and paragraphs in your text
- Password GeneratorGenerate strong, random passwords of any length
📊 Science
- Ohms Law CalculatorCalculate voltage, current, resistance, or power using Ohms Law (V=IR)
- Density CalculatorCalculate density, mass, or volume using the formula density = mass/volume
- Force CalculatorCalculate force, mass, or acceleration using Newtons Second Law (F = m × a)
- Subnet CalculatorCalculate subnet mask, network address, broadcast address, and host range from an IP address and CIDR prefix length