Category
Everyday Calculators.
Handy tools for the things you calculate every day. Looking for unit conversions? See Conversions.
Age Calculator
Find your exact age in years, months, days.
GPA Calculator
Calculate your semester or cumulative GPA.
Date Difference Calculator
Days, weeks, months between two dates.
Date Calculator
Add or subtract days, months, years from any date.
Time Duration Calculator
Add durations or find time between two times.
Business Days Calculator
Count working days between two dates.
Countdown Calculator
Days, hours, minutes until any future date.
Birthday Calculator
Age, next birthday, and day of the week you were born.
Work Hours Calculator
Total hours worked from start/end times.
Time Zone Calculator
Convert time between major world time zones.
Grade Calculator
Weighted grade average from assignments and exams.
Discount Calculator
Final price and savings after discount.
Unit Price Calculator
Compare cost per unit to find the best deal.
Bill Splitter Calculator
Split any bill evenly or by percentage.
Cost Per Use Calculator
True cost of any item based on how often you use it.
Fuel Cost Calculator
Trip fuel cost by distance and efficiency.
Password Generator
Strong random passwords with custom rules.
Height Calculator
Predict adult height from parents heights.
Concrete Calculator
Cubic yards of concrete for slabs and columns.
IP Subnet Calculator
Network address, usable hosts, and subnet mask.
Dice Roller
Roll any number of dice: d4, d6, d8, d10, d12, d20.
Voltage Drop Calculator
Voltage drop and wire gauge for electrical circuits.
BTU Calculator
BTU needed to heat or cool a room.
Square Footage Calculator
Area of rooms and spaces in various shapes.
Time Card Calculator
Total hours worked and pay from a weekly time card.
Horsepower Calculator
Engine HP from torque and RPM.
Stair Calculator
Rise, run, angle, and stringer length for stairs.
Ohms Law Calculator
Voltage, current, resistance, and power from any two.
Electricity Calculator
Monthly electricity cost for any appliance.
Shoe Size Conversion
Convert shoe sizes between US, UK, EU, and CM.
Molarity Calculator
Molarity, moles, and volume for chemistry solutions.
Molecular Weight Calculator
Molecular weight from a chemical formula.
Roman Numeral Converter
Convert integers to and from Roman numerals.
Roofing Calculator
Roofing squares needed for any roof size and pitch.
Tile Calculator
Number of tiles for any floor or wall area.
Mulch Calculator
Cubic yards of mulch needed for any area and depth.
Gravel Calculator
Cubic yards of gravel for any project.
Wind Chill Calculator
Feels-like temperature from wind speed and air temp.
Heat Index Calculator
Feels-like temperature from heat and humidity.
Dew Point Calculator
Dew point from temperature and humidity.
Bandwidth Calculator
Data transfer time from file size and connection speed.
Day of Week Calculator
What day of the week any date falls on.
GDP Calculator
GDP from C + I + G + net exports.
Golf Handicap Calculator
Golf handicap index from recent scores.
Tire Size Calculator
Tire diameter and sidewall from tire code.
Base64 Encode / Decode
Encode or decode text with Base64.
URL Encode / Decode
Percent-encode or decode URL strings.
Mileage Calculator
Gas mileage (MPG) from miles driven and gallons used.
Carbon Footprint Calculator
Estimate your annual CO₂ emissions from transport, energy, and diet.