Free Online Utility Calculators & Converters

Use our free online utility calculators and unit converters. Convert length, weight, temperature, area, volume, and more — all in one place, completely free.

• Unit Converter

  Free online unit converter. Convert length, weight, temperature, speed, area, and volume between metric and imperial units.

• Date Difference Calculator

  Find the exact calendar-day difference between two dates, including weeks, weekdays, weekends, and an anchored years–months–days breakdown.

• Work Hours Calculator

  Calculate total work hours and minutes from start and end times including breaks. Free timesheet calculator.

• Electricity Bill Calculator

  Estimate your electricity bill from monthly power usage in kWh with tiered progressive rate calculations.

• Fuel Cost Calculator

  Calculate fuel cost for any trip. Enter distance, fuel efficiency, and price per liter or gallon. Free online.

• Split Bill Calculator

  Split any bill equally or by item among friends. Add multiple items and people for a fair split. Free online.

• Length Converter

  Free online length converter. Convert meters, feet, inches, centimeters, kilometers, miles, yards and more instantly.

• Temperature Converter

  Free online temperature converter. Convert Celsius to Fahrenheit, Fahrenheit to Celsius, and Kelvin instantly.

• Weight Converter

  Free online weight converter and weight conversion calculator. Convert weight between kg, lbs, oz, grams, metric tons, stones and more instantly.

• Volume Converter

  Free online volume converter. Convert liters, gallons, milliliters, cups, teaspoons, tablespoons, pints and more.

• Area Converter

  Free online area converter. Convert square meters, square feet, acres, hectares, square kilometers and more.

• Speed Converter

  Free online speed converter. Convert km/h, mph, m/s, knots, Mach and ft/s instantly.

• Data Storage Converter

  Free online data storage converter. Convert gigabytes, megabytes, terabytes, bits, bytes, KB, GB, TB and more.

• Cooking Converter

  Free online cooking converter. Convert cups, tablespoons, teaspoons, fluid ounces, milliliters, pints and gallons.

• Commute Life Cost Calculator

  Calculate the total years of life and salary value lost to commuting. Enter your daily commute time and career years to see the shocking true cost.

• Sleep Debt Calculator

  Calculate your cumulative sleep debt and see how long it will take to recover your cognitive performance.

• Character Counter

  Count characters, words, and bytes in your text instantly. Free character counter with and without spaces.

• Password Generator

  Generate strong, secure random passwords instantly. Customize length, include uppercase, numbers, and symbols. Nothing is sent to a server.

• QR Code Generator

  Create a QR code from any text or URL instantly and download it as a PNG. Free, fast, and works entirely in your browser.

• GPA Calculator

  Calculate your GPA (Grade Point Average) easily. Enter your grades and credit hours to get your cumulative GPA.

• Wind Chill Calculator

  Calculate the wind chill factor and feel-like temperature. Enter air temperature and wind speed.

• Heat Index Calculator

  Calculate the heat index (feels-like temperature) based on temperature and humidity. Stay safe in hot weather.

• Grade Calculator

  Calculate your final grade based on assignments, tests, and exams. Find out what grade you need to pass.

• Day Counter

  Count the number of days between two dates or from today. Business days option included.

• Square Footage Calculator

  Calculate square footage of rooms, floors, or outdoor spaces. Supports rectangles, circles, triangles, and more.

• Age Difference Calculator

  Calculate the age difference between two people. Enter two birth dates to find the exact age gap in years, months, and days.

• Date Add & Subtract Calculator

  Add or subtract a whole number of days or weeks from today or any date. See the resulting date and weekday; zero days is valid.

• Cubic Feet Calculator

  Calculate volume in cubic feet. Enter length, width, and height to get cubic feet. Supports multiple units.

• Generation Calculator

  Find out what generation you belong to based on your birth year. Baby Boomer, Gen X, Millennial, Gen Z, or Gen Alpha?

• Energy Converter

  Convert between energy units: joules, kilojoules, calories, kilocalories, kilowatt-hours, BTU, and more.

• Pressure Converter

  Convert between pressure units: PSI, bar, pascal, atmosphere, kilopascal, and more. Fast and accurate.

• Time Converter

  Convert between time units: seconds, minutes, hours, days, weeks, months, and years. Fast and accurate.

• Grams to Cups Converter

  Convert grams to cups for cooking and baking. Supports flour, sugar, butter, rice, and many more ingredients.

• Kilograms to Pounds Converter

  Convert kilograms to pounds (lbs) quickly and accurately. Includes kg to lbs formula and conversion table.

• Feet to Meters Converter

  Convert feet to meters and meters to feet. Includes feet and inches to meters conversion.

• Centimeters to Inches Converter

  Convert centimeters to inches and inches to centimeters. Essential for height conversions and measurements.

• Millimeters to Inches Converter

  Convert millimeters to inches and inches to millimeters. Quick mm to inches conversion for engineering and daily use.

• Square Feet to Acres Converter

  Convert square feet to acres and acres to square feet. Instant area unit conversion.

• Square Meters to Square Feet Converter

  Convert square meters to square feet and square feet to square meters. Instant area conversion.

• Time Calculator

  Add or subtract time values (hours, minutes, seconds). Also sum multiple durations. Free online time calculator.

• Subnet Calculator

  Calculate subnet mask, network address, broadcast address, host range and total hosts from an IP address and CIDR prefix. Free online subnet calculator.

• Ohm's Law Calculator

  Calculate voltage (V), current (I), resistance (R), or power (P) using Ohm's Law (V=IR). Enter any two values to find the other two. Free online electronics tool.

• Paint Calculator

  Calculate how many liters or gallons of paint you need for a room. Enter room dimensions and number of coats. Free online paint coverage calculator.

• Concrete Calculator

  Calculate concrete volume in cubic yards or cubic meters for slabs, footings, and columns. Find how many bags of concrete you need. Free online tool.

• Military Time Converter

  Convert between standard 12-hour (AM/PM) and military 24-hour time format instantly. Includes a full military time conversion chart. Free online tool.

• Iranian Calendar Converter

  Convert dates between Solar Hijri (Shamsi/Jalali) and Gregorian calendar. Supports all Persian months. Used in Iran and Afghanistan.

Free Online Calculator