Calculators & Converters
Powerful calculators and unit converters for everyday needs. Unit conversions, business calculators, and utilities.
Free online calculators and unit converters for the numbers that come up in real life — a mortgage repayment, a body-fat percentage, a recipe scaled for eight, a currency of measurement you don't think in. Every calculator runs in your browser: nothing is uploaded, nothing is stored, and no signup stands between you and the answer.
Unit Converters
Length Converter
Convert between meters, feet, inches, kilometers, and more
Weight Converter
Convert between kilograms, pounds, ounces, and more
Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin
Volume Converter
Convert between liters, gallons, cups, and more
Area Converter
Convert between square meters, square feet, acres, hectares and more
Speed Converter
Convert between mph, km/h, knots, m/s and other speed units
Time Converter
Convert between seconds, minutes, hours, days, weeks, months, years
Angle Converter
Convert between degrees, radians, gradians, and other angle units
Energy Converter
Convert between joules, calories, kilowatt-hours, BTU, and more energy units
Power Converter
Convert between watts, kilowatts, horsepower, BTU/hour, and more power units
Pressure Converter
Convert between PSI, bar, pascal, atmosphere, torr, and more pressure units
Data Size Converter
Convert between bytes, KB, MB, GB, and TB
Fuel Efficiency Converter
Convert between MPG, L/100km, km/L, and more
Cooking Measurement Converter
Convert between cups, grams, tablespoons, ounces, and temperature
Unit Price Comparator
Compare unit prices across products to find the best value
Money & Business
Loan Calculator
Calculate loan payments and amortization schedules with detailed breakdowns
Mortgage Calculator
Calculate mortgage payments with PITI breakdown and amortization schedule
Compound Interest Calculator
Calculate investment growth with compound interest and regular contributions
Investment Return Calculator
Calculate potential returns and growth of your investments
Retirement Calculator
Plan your retirement with projected savings growth, monthly income using the 4% rule, and scenario comparison
Savings Goal Calculator
Calculate how much to save monthly to reach your financial goal
Debt Payoff Calculator
Calculate your debt payoff timeline using the snowball or avalanche method
50/30/20 Budget Calculator
Plan your budget using the popular 50/30/20 budgeting rule
Salary Calculator
Convert salary between hourly, monthly, yearly, and more
Hourly to Salary Converter
Convert between hourly wages and annual salary
Rent vs Buy Calculator
Compare the costs of renting vs buying a home to make informed financial decisions
VAT Calculator
Calculate VAT/GST quickly and easily
US Sales Tax Calculator
Add or extract US sales tax with 2025 state rates
Discount Calculator
Calculate discounts and final prices
Tip Calculator
Calculate tips and split bills between multiple people
Profit Margin Calculator
Calculate profit margins and markups
Advanced Profit Calculator
Calculate EBITDA, operating profit, net profit with break-even and scenario analysis
ROI Calculator
Calculate return on investment with simple, marketing, and comparison modes
Break-Even Calculator
Calculate break-even point with profit planning and margin of safety analysis
Meeting Cost Calculator
Calculate the true cost of meetings based on attendee salaries
Electricity Cost Calculator
Calculate electricity costs for appliances based on wattage, usage hours, and electricity rates
Invoice Generator
Create professional invoices instantly
Invoice Generator Pro
Create professional invoices with templates, client management, and PDF export
Quote Generator
Create professional quotes and proposals with PDF export
Receipt Generator
Create professional receipts for completed transactions
Expense Tracker
Track and categorize expenses with charts and CSV export
Project Time Tracker
Track time across projects and calculate earnings
Freelance Rate Calculator
Calculate your ideal freelance hourly, daily, and project rates based on income goals
Health & Fitness
BMI Calculator
Calculate your Body Mass Index with metric or imperial units
BMR/TDEE Calculator
Calculate your basal metabolic rate and daily calorie needs
Body Fat Calculator
Calculate your body fat percentage using US Navy method or BMI
Calorie Calculator
Calculate daily calorie needs, track food intake, and browse 50+ common foods
Macro Calculator
Calculate optimal protein, carbs, and fat intake based on your calorie goals and diet strategy
Ideal Weight Calculator
Calculate your ideal body weight using medical formulas
Water Intake Calculator
Calculate your daily water intake needs based on weight and activity
One Rep Max Calculator
Calculate your estimated one rep max (1RM) for any lift
Pace Calculator
Calculate running pace, time, or distance for training and races
Sleep Calculator
Calculate optimal sleep and wake times based on sleep cycles
Pregnancy Due Date Calculator
Calculate your due date and pregnancy milestones
Date & Time
Age Calculator
Calculate your exact age in years, months, days, hours, and more
Date Difference Calculator
Calculate the number of days, weeks, months, and years between two dates
Days Calculator
Calculate days until or since any event. Countdown to weddings, birthdays, and more.
Business Days Calculator
Calculate working days between dates with holiday support for multiple countries
Event Countdown Timer
Count down to birthdays, weddings, holidays, and special events
Timezone Converter
Convert times between different timezones
Math & Statistics
Percentage Calculator
Calculate percentages with 4 different modes
Percentage Change Calculator
Calculate percentage increase or decrease between two values
Fraction Calculator
Add, subtract, multiply, and divide fractions with step-by-step solutions
Scientific Calculator
Advanced calculator with trigonometry, logarithms, and scientific functions
Average Calculator
Calculate mean, median, mode, and more statistics
Mean, Median, Mode Calculator
Calculate mean, median, mode, standard deviation, and more statistics
Prime Number Checker
Check if a number is prime, get factorization, and generate prime numbers
Combinations & Permutations Calculator
Calculate nCr combinations, nPr permutations, and factorials with step-by-step solutions
Quadratic Equation Solver
Solve ax² + bx + c = 0 quadratic equations with step-by-step solutions and graph
Random Number Generator
Generate random numbers with presets for dice, coins, lottery, and more
Everyday Life
GPA Calculator
Calculate your semester or cumulative GPA with support for 4.0, weighted, and plus/minus scales
Grade Calculator
Calculate what grade you need on your final exam to reach your target grade
Recipe Scaler
Scale recipe ingredients up or down for any serving size
Carbon Footprint Calculator
Calculate your annual carbon emissions from transportation, energy, diet, and shopping
More tools
Ohm's Law Calculator
Solve for voltage, current, resistance, or power
CAGR Calculator
Calculate the compound annual growth rate between two values
GCF & LCM Calculator
Find the greatest common factor and least common multiple of any set of numbers
Ratio Calculator
Simplify ratios to lowest terms and solve proportions for a missing value
Ovulation Calculator
Estimate your fertile window, ovulation day and next period
Wind Chill & Heat Index Calculator
Work out what the temperature actually feels like from wind and humidity
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